Added support for the qCmd monitor packet command. Currently it can only do:

set logfile=<path>
set logmask=<num>

But this opens the door for us to do much more.



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@174258 91177308-0d34-0410-b5e6-96231b3b80d8