adding c* 1.2 client SSL support to a6x.
Merge branch 'master' of github.com:Netflix/astyanax
Merge branch 'master' of github.com:Netflix/astyanax.
Also, slightly reworking the SSL integration code to use a new object
called SSLConnectionContext. It's presence or absence (by being null or not)
in the ConnectionPoolConfigurationImpl determines whether to use SSL in
connecting to cassandra.
Merge pull request #149 from jasobrown/master

add client-side thrift SSL support to a6x