Direct screenwavemedia.com URLs support (issue #3766)

The first patch adds support for direct downloading from screenwavemedia.com URLs (by modifying the cinemassacre extractor). The second adds teamfourstar.com support on top of it.

**Warning**: the patches were not tested very well, and probably should not be accepted without review; I feel the code is quite inefficient with its multiple URL parsing and may not cover some corner cases.
Why have three methods instead of just three extractor classes?