SBFile: add a bunch of tests that should eventually work.

Summary:
It's really annoying and confusing to have to keep referring
back to earlier versions of this SBFile work to find the
tests that need to be added for each patch, and not duplicate
them with new tests.

This patch just imports all my tests.   A bunch of them don't
work yet, so they are marked to be skipped.   They'll be
unmarked as I fix them.

One of these tests will actually trip an assert in the SWIG
code now instead of just failing, so I'm fixing that here too.

Reviewers: JDevlieghere, jasonmolenda, labath

Reviewed By: JDevlieghere, labath

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D68433

llvm-svn: 374237