Return a std::unique_ptr from parseInputFile and propagate. NFC.

The memory management in BugPoint is fairly convoluted, so this just unwraps
one layer by changing the return type of functions that always return
owned Modules.
Refactored existing gdb-remote qProcessInfo tests into separate python file.

I'm about to add some more qProcessInfo tests so I wanted to first pull them out
of the monolithic TestLldbGdbServer test case class.

Related to http://llvm.org/bugs/show_bug.cgi?id=20755