jclouds config properties: accept camel or hyphen format

- previously, only accepted hyphenated format such as 
  brooklyn.jclouds.aws-ec2.private-key-file; now also accepts
  brooklyn.jclouds.aws-ec2.privateKeyFile.
- TODO: decide whether to support both of these or just one;
  suggest deprecating one!
Add ControlledDynamicWebAppCluster.CONTROLLER_SPEC
PortMapping: null checking
MySqlSshDriver.install fix: spilt yum installs

- On a CentOS 6.3 VM, the install of libgcc_s.so.1 failed with
  "Error: Protected multilib versions: libgcc-4.4.7-3.el6.i686 != libgcc-4.4.6-4.el6.x86_64".
  Therefore it didn't go on to next install of libaio.so.1 and 
  libncurses.so.5; easily fixed by splitting the install into two
  separate commands.
Merge pull request #594 from aledsage/jclouds-property-format

Jclouds property format