create system for parsing content from a request
create manager for parsing content based on content-type
create container for modelising parsed content
add container for modelising a field in a document
add validators for checking the type of a field
add additional validators that can be added to fields
add factory for creating content parser
decode json before parsing it
add content parser to flask app
add content parser to configuration resource
add 'size' parameter to length validator

matches strictly on exact size of value
remove custom error handling

removes information from traceback when exception is raised
add field types and validators to premacop namespace
split decoding from model mapping in formatter

premacop already does the decoding
fix minor code styling issues
add content-type when sending PUT or POST requests in tests
clean up cruft in device tests

remove redundant code and make tests a bit more clear to read
add premacop parser to device resource
add premacop parser to extension resource
remove cruft from line_extension tests