Fix Collections View

[rosiel]

Ticket: #31

To test this, you MUST install this exact version (not update to it, etc). Use this branch of the sandbox to deploy. (In its README there are testing instructions).

With this PR:

• The Collections view now filters on the core Model field, instead of the metadata-y Resource Types field.
• The Context for displaying Collections now 'includes default blocks' (it looked a little weird without it)
• The Context module's no longer locked to a specific commit, to fix a warning i was getting (Context module: "Menu Reactions" will not work because menu.active_trail has a different menu service provider.)
• For good measure (this is NOT active in the current install, see ticket #31 ), removed the core Islandora tags from this list, and corrected the Collection tag. This is so that we can use this file in the future if/when we remove Defaults.

[noahwsmith]

Full install trace: https://gist.github.com/noahwsmith/3ac13b9582a5fc7fa23cecd527a5d610

Looks good! My test collection shows on the "Browse Collections" page if the Model is "Collection" and it doesn't care about the Resource Type.

I'm happy to approve this for merging, but it sounds like there's a specific order of ops for Islandora-Devops/islandora-sandbox#19. I'm comfortable with you merging all those things in the correct order with the correct edits, @rosiel , if you're willing.

Thanks for doing this!

[noahwsmith]

Worked great for me!

[rosiel]

Great! The order of ops is:

• merge this
• update the linked sandbox PR (repoint the composer.json file, then update composer.lock)
• merge the sandbox pr