[#438] Fix (most) issues with terms on the record creation page

[fenekku]

To fix the deposit page, we had to revert our past changes to invenio-records-js and make different ones.

The real problem is that the ui-select (multiple option) library is buggy and unmaintained (~117 open issues): https://github.com/angular-ui/ui-select/issues?q=is%3Aissue+is%3Aopen+multiple&utf8=%E2%9C%93 . Additional bugs with ui-select multiple were uncovered when working on this issue which led us to abandon using ui-select multiple entirely. Instead, we

• Switch to array of ui-select / termselect for MeSH and FAST bc
  • uimultiselect doesn't initialize previously filled terms properly
  • the library is essentially unmaintained
  • we are moving away from angularjs
  • Zenodo has an example of this pattern that works with their Grants field
• Add termsselect template
• Add id to terms schema. Id is not required now, so that entered records on stage don't cause problem. After the fall meeting we will wipe data and require ids.
• Revert uiselect.html to how it was before.
• Update serialization of terms for UI
• Simplify running local development by having just 1 script to run.

Closes #438

[fenekku]

This is somewhat big so ask me questions if things are unclear. I tried to place a lot of explainer comments to help.

NOTE: There is one edge case that is weird: adding multiple terms and deleting the first one gives strange results, but this is the best we are going to get from the ui-select library at this point. :face_with_head_bandage:

I will deploy this tomorrow morning (might be more issues on stage, but I will need more energy to deal with them).