CAS-951 Upgrade to OpenSAML 2.x

CAS-999: In modifying the applicationContext.xml and reorganizing the service registry bit, a number of service ids in the xml were renamed and updated. That change broke a number of tests in ProxyControllerTests, specifically testExistingPGT() as the test specifically looks for a particular service id in the assert response.

This commit updates the test to use the new service id and adds a new test for not-authorized proxy authN. Since the merge has gotten into trunk and this is just a small extension of that commit, the change is pushed to the master branch directly.

CAS-1155: Switch the build to require JDK 1.6

CAS-1154: Updated missing maven plugin versions in the pom

CAS-999: per-service selection of username attribute to release...

CAS-1154: Updated missing maven plugin versions in the pom

CAS-999: Adjusted the javadoc for the username attribute to remove null as the returning value. Fixed issue with the default meta attr that was put as part of other available attributes.

CAS-999: Added several unit tests (and had to fix one as the result of the changes), improves javadocs and added the missing "final" keyword.

CAS-999: Fixed the issue where the registered service looked into its attributes by means of an equals() rather than contains(), noted by leleuj

Additional fixes are:
- Removed the opaque identifier constant
- Improve service validation logic to ignore anonymous service
- Added anonymous column to svc registry so that in conjunction with the username attribute, the logic can better be understood and diagnosed.

CAS-999: per-service selection of username attribute to release the principal id. Allows for opaque identifiers.

CAS-1150 : Update to the latest jasig-parent pom (34)

CAS-1144 Clean-up inspektr configuration

CAS-1141 : Improve OAuth module

CAS-1140 Additional monitors for vital CAS components.

Testing revealed that the memcached stats contain missing keys under some circumstances where the status description can be misleading.

CAS-1147- Refactor service authorization check to occur at the beginning of the flow

Per https://wiki.jasig.org/display/CAS/Code+Conventions:
 - Qualify instance variables with "this"
 - Use final wherever possible

New monitors:
 - ContextSourceMonitor (monitors LdapContextSource)
 - DataSourceMonitor (generic data source/pooled data source monitor)
 - EhCacheMonitor
 - MemcachedMonitor

Minor refactoring of existing monitors to conform convention of required versus optional parameters.