Conflicts:
	src/async.h
	src/statement.h
	wscript

* remove 0.2.x Buffer compatibility

Conflicts:
	wscript

enable usage of boost threads instead of direct posix/pthreads usage - all tests are passing on OS X 10.7 with boost 1.47 - todo: test on linux - refs #48

add a threading compatibility shim - likely cleaner ways of doing this but we don't want to depend on boost threads unless we really have to for now

default to building against internal version of sqlite, and allow disabling by passing option to --with-sqlite3. Also update to latest sqlite version for internal copy - closes #43

Fix build with system-wide sqlite3 library

refs #29

refs #29

provide option to build and link against internal sqlite with --internal-sqlite - should consider making this default if needed - closes #13