update URLs to use /api/ instead of /querymodule/v0
Merge branch 'master' of https://github.com/CSSIP-AIR/PatentsView-API
Add XML example and update patent query field list
update inventor field list
add cpc subsections
add uspc mainclass query
add disclaimer
Merge pull request #3 from jotok/master

Updates to documentation (CPC Subsection, USPC Mainclass)