specify TFramedTransport explicitly

Thrift 0.9.1 changed its default transport to TBufferedTransport where
cassandra uses TFrameTransport.
Fix it by specifying the transport at connection creation time.
regenerate thrift code, avoid double buffer-string conversion

This regenerates the cassandra.thrift definition file with the
thrift 0.9.1 compiler + wade's readBinary patch [1]. This patch
makes the autogenerated code use readBinary() to read binary fields
instead of using readString(), avoiding a spurious
buffer -> string -> buffer conversion when parsing cassandra responses.

1: https://issues.apache.org/jira/secure/attachment/12599272/0001-read-binary-strings-with-readBinary-v2.patch
Merge pull request #95 from racker/supportThrift0.9.1

support thrift 0.9.1, improve performance