Enable route paths as symbol and optional leading '/'

So far, all routes must be strings and the first character has to be
slash - '/'.

This commit enables the following:
- routes can be symbols too
- when path is string, leading slash character is optional
Merge branch 'more_route_path_options' of git://github.com/bruno-/busker into bruno--more_route_path_options

Conflicts:
	lib/busker.rb
Merge branch 'master' of github.com:pachacamac/busker
merge and cleanup