Improve detection of OS in OsTasks

Confirmed that OSs in EC2 live test return sensible values
Fix EC2 live test and always show 'unknown' when OsTask input empty.
Add note to handlebars-1.0.rc.1.js about why updating it is difficult.
Adds documentation for driver copyResource and copyTemplate methods
First pass at brooklyn reloading brooklyn.properties (server side, no safety checks etc)
Reload loacations on brooklyn.properties reload
Reload ManagementContext config and location registry on reload of brooklyn.properties
Added basic (failing) test for reloading brooklyn.properties
Renamed LocalManagementContextEst
Created override of LocalManagementContext constructor to take a BrooklynProperties.Factory.Builder, to allow reloading of brooklyn properties from supplied property files
Removed spurious test class
Implemented NonDeploymentManagementContext.reloadBrooklynProperties()
fix test which fails if local hostname is misconfigured (which some rogue wifi points like to do!)
enhance the JmxmpAgent so that if an rmi registry port is passed in, it also opens an rmi registry,
allowing local agents to connect using rmi in addition to jmxmp for external use,
and a new JmxAgentMode.JMXMP_AND_RMI to allow clients to use this.
Upgrade git-like-cli:0.3 to io.airlift:airline:0.6

- project has been renamed to airline
- behaviour seems to be identical in the new version
- note that for 0.7, it looks like there'll be another package rename
  from io.airlift.command to io.airlift.airline:
  https://github.com/airlift/airline/pull/25
some cleanups to ensure PortRange coercions are set, and give better error messages on errors i encountered
Merge pull request #1154 from sjcorbett/further-os-details

Improves detection of OS in OsTasks
Merge pull request #1169 from aledsage/refactor/gitLikeCli-to-airline

Upgrade git-like-cli:0.3 to io.airlift:airline:0.6
Jmx agents: register shutdown hook
Jmx agents: include agentmain()

- allows the agent to be started *after* the JVM is already running