[BZ 1022943] Ability to trigger update of plugins on agents from UI and API
This is stage 1 of the series of commits to enable more user-friendly
handling of plugin updates.

It provides basic support for triggering updates of plugins on agents
by calling server-side APIs/GUI.
Merge remote-tracking branch 'origin/master' into bug/1022943

Conflicts:
	modules/enterprise/server/itests-2/src/test/java/org/rhq/enterprise/server/test/TestAgentClient.java
	modules/enterprise/server/jar/src/main/java/org/rhq/enterprise/server/agentclient/AgentClient.java
[BZ 1022943] Added ability to check status of plugin update on agents
Merge remote-tracking branch 'origin/master' into bug/1022943

This is to have the fix for BZ 1076389 (which blocks BZ 1022943) in this branch.
[BZ 1022943] Fixes to PluginCriteria
[BZ 1022943] Reporting changes of plugin deployments
note in the javadoc that the deploy* methods are synchronous.
[BZ 1022943] Added a new REST endpoint for working with agent plugins.
First cut of a Aerogear-Unified-Push-Server alert plugin.
BZ 1090448 - make the remote agent install UI more pretty
[BZ 1076104] - Fix the itest failures in plugin purge tests.
BZ 1090448 - this got munged - need to encode in UTF-8.
Merge master into bug/1022943 reflecting disappearance of plugin purge
[665508] rhq:url-archive, rhq:archive should support destinationFile/destinationDir
- Fix API back-compat issues in DeploymentData constructors
- Fix ambiguous constructors issue in DeploymentData when using various null params
- Fix some related jdoc
- Update our code base to not use deprecated calls in DeploymentProperties
  and DeploymentData.
[BZ 1092507] Globally uncaught exception when selecting an area which doesn't contain data in unfolded graph. Zooming in on range of no data (NaN) causes the lowestValue to become null because there is no low value (there are no valid values at all). This scenario was solved by assigning the measurement definition UOM when no valid values are available.
BZ 1091172 - get remote API to work with remote agent install
[BZ 1022943] Fix delay selection dialog in UI.
[BZ 1022943] Remove remnants of plugin purge from criteria class and REST.
Merge remote-tracking branch 'origin/master' into bug/1022943
Some cleanup and externalization of settings.
Merge pull request #25 from pilhuhn/alert-ups

Aerogear UPS alert sender plugin