Clear button works.

Tests added
Responding to review

Fixed bug introduced before previous commit - can now remove added relationships.

Added clear button to top of deployer bar summary, as well as commit confirmation.
Merge branch 'develop' into clear-changes

Require features from in-progress work.
Clear inspector when clearing ECS

Use correct container.

Hide 'deploy' message on clear

Minifying variables.
Merge pull request #508 from makyo/clear-changes

Add ability to clear ECS changes.

You can now clear the changes staged in the ECS and have them removed from the database.  Note: this does not include config-changed entries in the ECS: that will be a future branch.