Move source code of all Meterpreter extensions to a common target
directory during build, so that tests that apply to all extensions won't
need to be updated when a new extension is added.
Use this to apply the version compatibility checks to all extensions.
Check JavaPayload and Java Meterpreter against version incompatibilities
for Java 1.2, 1.3, 1.4, 1.5, and 1.6.
Note that webcam_audio_record is currently excluded from the checks, as it
uses Sun proprietary API for building the WAV file and is therefore
failing the build (and will most likely crash Meterpreter if run on a JVM
of version 1.4 or later that is not based on the Sun/Oracle JVM).
Possible workarounds (apart from either removing the module or changing it
to produce empty files when WAV creation is not supported) include
implementing the WAV file writer ourselves or providing raw PCM files
instead.
