Pull identified locale property and method up into AbstractLocaleGuesser

Conflicts:
	LocaleGuesser/BrowserLocaleGuesser.php
	LocaleGuesser/QueryLocaleGuesser.php
Add SubdomainLocaleGuesser
Add subdomain guesser to docs
Add configuration parameter for region separator
Merge pull request #71 from kevarch/issue/26/SubdomainLocaleGuesser

Add Subdomain Locale Guesser