Making the user data fields mapping to Shibboleth variables configurable.
Changing configuration variables to make them independent.
Changing example configuration to match defaults.
Recovering flexibility to add new fileds mapping with example.
Merge pull request #4 from TiagoTT/master

Making the user data fields mapping to Shibboleth variables configurable.
change :fields -> :info_fields and omit :email field as default
increment version
add explanation message to :debug outputs
add an advice to deal with the devise integration
change the reference of the devise configuration
the related devise documents are properly updated
Merge remote-tracking branch 'upstream/master'

Conflicts:
	lib/omniauth/strategies/shibboleth.rb