feat: depend on ddev/ddev-solr, fixes #40

[mkalkbrenner]

The Issue

• ddev-drupal-solr is obsolete #40

How This PR Solves The Issue

TODO:

• depend on ddev/ddev-solr
• migrate existing core
• add drupal-specific stuff to ddev/ddev-solr
• README
• tests

Manual Testing Instructions

ddev add-on get ddev/ddev-solr
ddev add-on get https://github.com/ddev/ddev-drupal-solr/tarball/ddev-solr
ddev restart

Automated Testing Overview

Release/Deployment Notes

[mkalkbrenner]

@rfay @bserem @tyler36
Before I continue to work on the todos, it would be great to get some feedback or thoughts on this approach and the direction outlined in #40

[bserem]

@mkalkbrenner as I understand end-users will have to install both addons, and that's it more or less. Or perhaps we can add the dependency in the pre_install_actions (not sure if this is possible).

The PR definitely makes things cleaner, but it also makes me wonder:
is this addon needed after the migration has happened?

[mkalkbrenner]

The dependency is already declared in install.yaml.

And yes, I think we should keep both modules. All drupal-specific stuff should be moved here:

• documentation
• commands to install/deploy ...
  • jump-start configset
  • fresh generated configset
  • Solr hosters' drupal-specific configsets
• multisite search
• support for search_api_solr_nlp
• ...

This way dev-solr will have no relation to drupal anymore and could be the base for ddev-typo3-solr, too.

[stasadev]

Rebased and resolved conflicts.