docs(guide/$location): describe workaround for collocated apps

When using Angular in the root of a domain with HTML5 URLs
where there are links to external paths within the same directory,
the `otherwise` route handler will catch these external files.
This can be fixed by prefixing '.' onto the links to URLs that should
be handled by angular routing.

Original Issue: #3520
Example of Fix: http://fiddle.jshell.net/fgHf6/3/

Closes #3555

docs/content/guide/dev_guide.services.$location.ngdoc

@@ -321,6 +321,14 @@ reload to the original link.
   Example: `<a href="http://angularjs.org/">link</a>`
 - Links starting with '/' that lead to a different base path when base is defined<br>
   Example: `<a href="/not-my-base/link">link</a>`
+  
+When running Angular in the root of a domain, along side perhaps a normal application in the same
+directory, the "otherwise" route handler will try to handle all the URLs, including ones that map
+to static files.
+
+To prevent this, you can set your base href for the app to `<base href=".">` and then prefix links
+to URLs that should be handled with `.`. Now, links to locations, which are not to be routed by Angular,
+are not prefixed with `.` and will not be intercepted by the `otherwise` rule in your `$routeProvider`.
 
 
 ### Server side