Fix searching by extern_uid for LDAP to be case-insensitive
Updated contribution guidelines to specify MRs should be to master.
 Merge branch 'documentation/update_mr_contribution_section' into 'master'

Update Contribution Guidelines: Specify Merge Request To Master

There have been occasions where contributors submitted merge requests to stable branches thinking that was the way to get changes into specific releases. This results in wasted time and effort of the GitLab team responding to the merge request requesting that it be to master, as well as the developer who needs to redo the changes.

This merge request very simply updates the contribution guidelines to specify that MRs should only be to master, and that getting changes into stable branches will be determined by the GitLab Team.

cc @JobV
Clearfix on well-lists. Pages affected:

Pages affected:
- admin/groups#show
- admin/projets#index
- admin/users#index
- dashboard/issues#index (on small screens)
Improve alignment of labels in .well-list items
Add a rake task that drops all tables
Drop all tables before restoring a PostgreSQL DB

Invoking 'db:schema:load' turned out to be a bad idea: when downgrading
an existing GitLab installation, the schema of the newer version would
be preserved when trying to import the old version.
Use omniauth nickname as the username for LDAP

Before there was a bug in omniauth-ldap which prevented samaccountname
showing up as a possible username for new LDAP users. Thanks to upstream
fixes, we no longer need to work around this bug.
 Merge branch 'ldap_nickname' into 'master'

Remove omniauth-ldap nickname bug workaround
Refactor project watchers collecting.
Merge remote-tracking branch 'origin/rake_drop_tables'

Conflicts:
	CHANGELOG
Merge pull request #6644 from tombruijn/list-item-name-spacing

.well-list item name spacing fix Follow up on #6643
Merge pull request #6317 from jirutka/fix-ldap-dn-case

Fix searching by extern_uid for LDAP to be case-insensitive
 Merge branch 'refactor_project_watchers_notifications' into 'master'

Refactor project watchers notifications