Major refactor of the access module The first step to sanity is a leap into the unknown? Create an object to represent the access checks for each module instead of a bunch of loose functions. Converted all views and params.py to use the new access checker. Main differences: * arguments to a checker can be passed by using a tuple * checkers are referenced by string, rather than directly * the Checker constructor handles merging with child views Patch by: Sverre Rabbelier