Validate the users settings conf prior to deploy

def check_settings():
    """
    Validate the users settings conf prior to deploy
    """
    valid=True
    if not get_version() >= '1.0':
        print "FABRIC ERROR: Woven is only compatible with Fabric < 1.0"
        valid = False
    if not env.MEDIA_ROOT or not env.MEDIA_URL:
        print "MEDIA ERROR: You must define a MEDIA_ROOT & MEDIA_URL in your settings.py"
        print "even if plan to deploy your media separately to your project"
        valid = False
    if not env.TEMPLATE_DIRS:
        print "TEMPLATES_DIRS ERROR: You must define a TEMPLATES_DIRS in your settings.py"
        valid=False
    if env.DEFAULT_DATABASE_ENGINE in ['django.db.backends.','django.db.backends.dummy']:
        print "DATABASE SETTINGS ERROR: The default database engine has not been defined in your settings.py file"
        print "At a minimum you must define an sqlite3 database for woven to deploy,"
        print "or define a database backend is managed outside of woven."    
        valid=False
    if not valid: sys.exit(1)