Add perf trace
Merge from dev
Reduce chance of session (connection) switch in MCIMAPAsyncSession.cc
Revert perf stuff
Don't install cmake on travis
Merge pull request #797 from yuklai/master_sessionSwitchReduce

Reduce chance of session (connection) switch in MCIMAPAsyncSession.cc
Fixed some memory leaks
Fixed memory leak (fixed #794)
Updated to libetpan 01b3b3b83d2b8651c0279018d4e48061509494eb