Moves try/except for ProcessingExceptions to a function decorator.
Moves APIManager docstring from __init__() function to class.
Fixes #128: allows disjunction of filters when searching.
Merge pull request #163 from bpedman/scalar-proxy-attrs

Association proxy fails if the remote attribute is a column and not a relationship
Fixes docstring formatting.
Uses NO_CHANGE in examples and documentation.
Add hybrid_properties to list of columns from helper

When performing a post to create a new instance we were not allowing the user to
set values for a hybrid_property since it was not in the set of defined columns.
However, a patch/put request worked just fine to update the attribute. This
change fixes it so you can set the hybrid_property attribute during a post
request.