adds ext section for better dependency managment, replaces deprecated…

[jkwiecien]

This fixes #28 by:

• updating gradle to the recent one
• updating support lib to the recent one

In the process also updated build tools, compile and target sdk, and added some shared variables in global build.gradle

[renaudcerrato]

Why is that required ?

[renaudcerrato]

Thanks @jkwiecien, but there's quite a few cleanup required before merging that PR :

• Not sure why you need the plugin com.github.dcendents.android-maven, this is not necessary IMO
• Your commit includes a lot of white space change in several places, including java files. This is not relevant to the PR
• You added a gradle/wrapper folder into the /sample, which is not needed.

[jkwiecien]

How would I solve the whitespaces problem? You probably used some custom code style formatter while I'm using the default AS one. Is your custom formatter part of the repo?

[renaudcerrato]

@jkwiecien : just don't git add those java files ? It looks like there's no source file update required, right?

[jkwiecien]

There is for sure at least one source file updated on purpose

[jkwiecien]

I just checked. There were files updated for a reason. Just the change got lost in a crowd of white spaces, because as said before, you were using some custom format. You'll have to add it to the repo if you want me to fix it.

[renaudcerrato]

Mmmm... I'm not using any custom formater for the exact reason we're experiencing now : that mess with PR when contributing. Let's forget about the whitespaces, but what's about the unwanted plugin and gradle folder?

[jkwiecien]

Deleted the unwanted gradle files from sample module. You should double check your code style formatter because I' pretty sure it's a custom one.

[jkwiecien]

This is the part that was crashing, I'm not sure why the conditions were here, maybe you got some valid reasons, however, some of these classes/methods are not accessible anymore