Swap requestargs and requestquery

[jace]

Ticket #132 was closed prematurely citing existing use. requestargs continues to cause confusion as it suggests that request.args will be consulted, while actually consulting request.values. To fix:

1. Rename requestargs to requestvalues
2. Temporarily alias it back to requestargs
3. Audit all code that is using requestargs for POST requests and switch to requestvalues or requestform as appropriate
4. Drop the alias and rename requestquery to requestargs (retaining an alias)