MBS-4115, Schema changes for .png/.gif support.
Adding descriptions to collections
Removing unused preview bit
Preparing schema change branch for 2013-05-15
Rename setup_test_db_for_selenium.pl → script/setup_development_db.pl.

Now that selenium tests have been removed, a script to set up a
database for selenium is no longer needed.  However, the script is
still useful as a general way to set up a minimal database.  I changed
it to operate on the production/development database instead of a test
database.
Add SQL update scripts which deduplicate tracklists.

This changes made by these scripts are:
  1. replace tracklist column in tracks with a medium column
  2. make copies of each track so a track is not re-used on multiple media
  3. add gid column to the track table and generate uuids for each track
  4. add track_gid_redirect table
Preparing schema change branch for 2013-05-15
Fix syntax error in upgrade.sh
MBS-5314: Drop the work.artist_credit column

This column has been long deprecated (and only contains NULL).
MBS-5302: ISNI support for artists and labels
Revert changes to caa/CreateViews.sql

This change does not pertain to this branch.
Fix tests
Reimplement merge strategy to be O(1) rather than O(n)
Add ON_ERROR_STOP 1 to the upgrade script
MBS-5917: schema changes for MBS-4756, move transclusion table to the DB
MBS-5917: table export changes for MBS-4756, move transclusion table to the DB
MBS-5917: upgrade script for MBS-4756, move transclusion table to the DB
Merge branch 'master' into schema-changes-2013-05-15

* master: (169 commits)
  Do not rebuild Carton on production
  Correctly discard carton.lock changes on prod
  Do not allow modifying collections a user does not own
  MBS-5901: typo in MBS-3990 fix
  Use a map instead of a for loop when constructing discs in Serializer::JSON::2::Medium.
  Revert "Fix Data::Editor tests to account for collection subscriptions"
  Add cover-art-archive fields to WS::2::JSON discid lookup tests.
  Fix Data::Editor tests to account for collection subscriptions
  Use sorted_children instead of sorted_attributes
  Use twice as much code for sorting
  Update translations from transifex.
  Update .pot file.
  Readded validateEntities flag reset after callback.
  Undid most of last 2 commits - will be fixed by bitmap at a later date.
  Patch from bitmap, fixing batch add.
  Fixed batch add issues where an entity self-links.
  MBS-5887: show edit medium edits with only number changes
  Added test
  Adding lyricsnmusic to the whitelist
  MBS-3990: add line comment about the cookie time
  ...
MBS-5528: Rename short_link_phrase to long_link_phrase
Update reduplicate tracklist sql changes + test data dump script.

- Also update tracks attached to a single tracklist in 20130220-reduplicate-tracklists.pl
- Also replace the track insert/delete triggers in 20130220-update-track-trigger.sql
- Output tracks in script/release-group-sql-dump.pl, and dump link tables in the correct order.
- Include some temporary scripts (resetdb.sh, cleandb.sh) useful during development of this branch.