Rename entities to starfall_*

The names were inconsistent and long. We know it is for gmod and we know
they are wire entities.
The only useful information in the prefix was 'starfall', which was
kept.

Close #89
Merge pull request #95 from Xandaros/iss89

Rename entities to starfall_*
Fixed pcall vars being global. Now local.

Fixes #93
Merge pull request #97 from awilliamson/iss93

Fixed pcall vars being global. Now local.