Migrated getting started page and removed outdated text. Updated some links.

Author: m-miedema

docs/community/gettingstarted.md

@@ -1,4 +1,120 @@
-## Under development
-We're still building this section of the guide, so stay tuned (or help!)
+# Getting Started!
 
+First of all: thank you! 
 
+Contributions can be made in different ways, not only code! As we follow
+the
+[all-contributors](https://github.com/all-contributors/all-contributors)
+specification, any contribution will be recognised accordingly.
+
+Follow these steps to get started:
+
+1.  Have a look at our [code of conduct](/community/CODE_OF_CONDUCT).
+2.  Make sure that you have a GitHub account. You can set up a [free
+    GitHub account](https://github.com/); here are some
+    [instructions](https://help.github.com/articles/signing-up-for-a-new-github-account).
+3.  If you intend to contribute code and/or use the `physiopy` packages
+    in any way, check that you have `git` and `pip` installed on your
+    system. Then install the package as a developer. This will let you
+    run the program with the latest modifications, without requiring to
+    re-install it every time.
+
+### Note
+The following instructions are provided assuming that python 3 is
+**not** your default version of python. If it is, you might need to use
+`pip` instead of `pip3`, although some OSs do adopt `pip3` anyway. If
+you want to check, type `python --version` in a terminal.
+
+
+Linux, Mac, and Windows developer installation
+----------------------------------------------
+
+Be sure to have `git` and `pip` installed. Fork the phys2bids repository
+in GitHub, then open a terminal and run the following code to clone the
+forked repository and set it as your \`origin\`:
+
+    git clone https://github.com/{username}/{physiopy-package}.git
+    # or in case you prefer to use ssh:
+    git clone [email protected]:{username}/{physiopy-package}.git
+
+We also recommend to set up the physiopy/{physiopy-package} repository as
+*upstream*. In this way you can always keep your main branch
+up to date with the command *git pull upstream master*:
+
+    cd {physiopy-package}
+    git remote add upstream https://github.com/physiopy/{physiopy-package}.git
+    git pull upstream master
+
+### Basic installation
+
+If you use python frequently, or you are a python developer, chances are
+that all the necessary dependencies are already installed in your
+system.
+
+Go to a physiopy package directory (e.g. the `phys2bids` folder) and execute the command:
+
+    pip3 install -e .
+
+### Full developer installation
+
+If it's your first experience as a python developer, or you just want
+to be sure that you have everything you need to collaborate with us, you
+can install `phys2bids` with all the other packages that we frequently
+use during development in one step!
+
+Go to a physiopy package directory (e.g. the `phys2bids` folder) and execute the command:
+
+    pip3 install -e .[all]
+
+This will install:
+
+> -   `phys2bids` as an editable package, which means that you can
+>     modify the program and run it without having to reinstall it every
+>     time!
+> -   All `phys2bids` dependencies.
+> -   All **interface** modules, that deal with the interfaces for all
+>     the file formats.
+> -   All **style** modules, such as `flake8`, to help you linter the
+>     code!
+> -   All **documentation** modules, like `sphinx`, so that you can
+>     build the docs locally before submitting them.
+> -   All **test** modules, like `pytest`, in order for you to test your
+>     code locally before committing it!
+
+### Check your installation!
+
+Type the commands:
+
+    cd phys2bids/tests
+    pytest
+
+This will execute the tests locally and check that your phys2bids
+installation works properly.
+
+    pytest
+    =================================== test session starts ===================================
+    platform win32 -- Python 3.8.6, pytest-6.1.1, py-1.9.0, pluggy-0.13.1
+    rootdir: C:\Users\sento\phys2bids, configfile: setup.cfg
+    plugins: cov-2.10.1
+    collected 61 items
+
+    test_acq.py .                                                                        [  1%]
+    test_bids.py ................                                                        [ 27%]
+    test_integration.py ...                                                              [ 32%]
+    test_phys2bids.py ...                                                                [ 37%]
+    test_physio_obj.py .......                                                           [ 49%]
+    test_txt.py ..................                                                       [ 78%]
+    test_utils.py ...........                                                            [ 96%]
+    test_viz.py .x                                                                       [100%]
+
+    ================================= short test summary info =================================
+    XFAIL test_viz.py::test_plot_trigger
+    ======================== 60 passed, 1 xfailed in 142.58s (0:02:22) ========================
+
+Do **not** worry if there is a xfail error in the log. This happens when
+we know that a test will fail for known reasons, and we are probably
+working to fix it (see
+[here](https://docs.pytest.org/en/latest/skipping.html#xfail-mark-test-functions-as-expected-to-fail).
+However, if you do encounter any other error, check that you have all
+the extra dependencies installed and their version meets `phys2bids`
+requirements.