Token auth: make lifetime a string with choices, update inline doc
Token auth: fix formatting, add description for lifetime
Valued param cleanup choices: convert to_sym through to_s

The value may be a number, which cannot be converted to a symbol
directly, so we have to convert it to string first.
Token auth: leave lifetime verification on the valued parameter

Parameter choices are checked in HaveAPI even before an action
is invoked.
Token auth: make the default query parameter name less intrusive

When using resource named AuthToken, then sending it over GET
would result in it being considered as a token. Therefore,
the default query parameter name was prefixed with underscore.
Action AR output: call getter method for all attributes

This is needed because attributes() does resolve enum values
and returns integers instead.