Attaching two patches to make the current urlparse library, especially 
the relative url parsing and urljoin  to be RFC3986 compliance.
I have included all the tests prescribed in RFC3986 and verified them 
to pass with the patches.

Our parsing functionality of netloc (to 
username,password,hostname,port) is same as what RFC3986 specifies. It 
uses the term 'authority' instead of 'netloc'. I did not feel the need 
for name change. If required, it can done.