Added initial version of FindSentinels and PatternMatch-extras
(dependency).
Added initial version of the sentinel checker and
a suite of tests to run. FindSentinels.cc still needs
to incorporate information from the iiglue pass and store
its results rather than simply printing them.
Merge branch 'master' into null-terminated-checker
Finished the merge, and updated SConstruct files in order to
compile and run everything. I still need to update FindSentinels
to use the IIGlueReader, and then decide how to report my output.
Then I'll need to add the .actual files for each of the tests.
Cleaned up the FinSentinels code based on discussion
from today's meeting, added comments to each of the tests.
Minor white-space tweaks for consistent brace style.
Restructure depth-first search to more clearly document what *exactly*
each part is checking for.
Several other code clean-ups.

Biggest change is to refactor three matching patterns into a single
big pattern.  Also changed many errs() output messages into dbgs()
messages, since they really are used for debugging, not to report
errors to the user.
Cleanup pass over Alisa's scons build script changes.
Tell Emacs to use the same indentation style that Alisa likes.
Remove trailing whitespace at ends of lines.
Clang does not seem to care for some RHEL6 C++ headers.  So use
gcc-4.9 for Emacs inline syntax checking instead.  That's reasonable,
since we're already using for the actual compilation.
Made printing work correctly, verified changes from
previous modifications to FindSentinels. I'll clean up
the code a little bit more in the next commit and then
submit a pull request.
Updated documentation and changed  a few variable names
for readability in the print method - also removing the -debug
flag in SConscript since I didn't mean to commit that change.
I ran my regression test suite and adding documentation and changing
variable names did not manage to break anything. Ready for pull request.
Made changes requested to resubmit pull request - only minor
stylistic changes, no logic changes.
Remove a space before a tab.
Remove iiglue executable; binaries don't belong in source control.
Avoid an unnecessary type mismatch warning.
Ignore "json" subdirectory and LLVM bitcode assembly files.

All of these are generated from other files, so none belong in git.
Merge pull request #2 from AlisaMaas/null-terminated-checker

Null terminated checker