CDBConverter does not recognise Latitude with prefixing 0.

[keeper74]

Minor issue, I think..

OGC CDB 1.0 specifications states that the latitude directory starts with N or S, followed by 2 digits. So a latitude of 1 degree N is N01. CDBConverter ignores such a directory. Renaming it to N1 works, but contravenes the CDB specs.