Merge pull request #158 from eads/0.9-beta6

add ability to install requirements during install and newproject
Merge pull request #159 from eads/0.9-beta6

update docs to reflect release
Merge branch '0.9-beta6' of github.com:newsapps/flask-tarbell into 0.9-beta6
make requirements message more useful, add _base to reqs search path for backwards compatibility