SCHEMA-906. Skip the cassandra-maven-plugin and hbase-m-p correctly in cassandra submodule.

issue: https://jira.kiji.org/browse/SCHEMA-906
review: https://review.kiji.org/r/2100
Preliminary work for this.
Updates CDH5 version. Begins hacking security manager.
Adds a UserPermission constructor to the bridges.
Incremental improvements.
Disables KijiHTablePool. Fixes some tests.
Fixes some pom.xml style. HConnection is now unmanaged.
Fixes TestFormattedEntityIdRowFilter.
Fixes for numerous tests.

Mostly consist of KijiClientTest tweaks.
Uses a version of TestProtocolBuffers.java compiled with protoc 2.5.0
Rolls back the change to the TestHBaseSystemTable tests.
Adds getHConnection to HBaseFactory.

Requires an update to fake-hbase.
Uses new fake-hbase HConnection.
Adds an issues section to the README.md
Make kiji-schema-extras compile. Fix some checkstyle.
Fixes some checkstyle and find bugs errors.

Comments out more code to do this and uncomments copyrights.
Restores GenericTableMapReduceUtil since MR needs it.
Removes an extraneous fake-hbase dependency.