[Iss #31] Updated version number to 0.9.

The last release of BAP previous to the move to GitHub was 0.8.
The current release is 0.9.  We will move to 1.0-alpha once we
are feature complete with 0.8:
 - Disassembler
 - Lifting for x86 and ARM
 - CFG generation
 - SMT binding
 - Python bindings.

See issue #31 history for discussion.