add unit test
remove test
add rspec tests
better exception management
* refactor
** Settings is now a singletone
** expanded path for settings in the configfile for
  :build, :install, :local, :repos and :tests
   - :packages[package][section][env][key]
   - :packages[package][section][key]
   - [section][env][key]
   - [section][key]
** little improvement in exception handling
* rspec for settings now pass