[thrift] Make TTransportException::getType const throw()

Summary: const so that catching via "catch (const TTransportException& e)" works
  properly, and throw() for good convention.
Reviewed By: mcslee
Test Plan: still compiles
Revert: ok


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665403 13f79535-47bb-0310-9956-ffa450edef68
1 file changed