rename CdnFacadeProvider to CdnFacade
fix namespace by renaming provider to providers
fix a small typo
split the url into protocol and domain in the condig file

and compoes the url in the provider factory
it will make it easy to to generate assets urls from the asset helper function
move the threshold from the aws s3 specific scope to the global function scope
in the provider factory
add the facade helper function in the CdnFacade class
change in structure

remove the reading of the configurations from the CdnFacade class to the Factory (to be only place responsible on reading the config file and checking nothing is missing) and calling the factory from the CdnFacade (same like in the cdn manager) to create and return the corresponding provider class
check domain and protocol before using them (trim and slashes)
and add the url generator function to the interface
and updating some comments on the way
remove slashes from begging and ending of the path
create CdnHelper class and move the getConfig function to it

this class is to hold the shared function between the cdn class and the Cdnfacade class
update the read me file