Cleanup a bunch of warnings.

Lots of methods were supposed to return bool but were returning nothing,
which is undefined behavior. Make them all return void as they aren't
checked anywhere anyways.

While here, remove a completely unused method.
Make the indexerThread return a value.
Return NULL.
Fix runtime errors when built with clang.

Looks like matchedIds was being removed out from under this somehow. Allocate
the list during searchAlpha and return it, instead of passing it in and working
with it in searchAlpha.
Fix shenanigans introduced in previous commit.

There was no need to do things like this. Just create the list and return
it normally.
Merge pull request #4 from MITRECND/cleanup

Cleanup and fix for clang.

Approved by: Murad