bulkdelete: add basic integration test

This adds a basic integration test for bulk-deletion of docs

COUCHDB-2462
Fix ACE document editor cutting off long lines of code

Closes COUCHDB-2454
Enable passing a single test to nightwatch

You can now pass single testfiles to nightwatch which makes
development of tests easier and faster.

Example:
`grunt nightwatch --file="createsDatabase"` launches the
createsDatabase.js testfile in app/databases/tests/nightwatch

Happy testing!
Shouldn't throw Ace Editor js error

To reproduce:
1. Select a database and select the "+ New View" option from the
dropdown on the All Documents item.
2. Click on "Databases" in the left sidebar.

Before, this caused a JS error to occur.

Nightwatch test added to confirm this fix.

Closes COUCHDB-2468