Fix incorrect data type linking for request params of entity types

[serggl]

This is a fix for #507.

Few moments were changed:

1. Refactored to use a single method for parsing entity names (see recent comments to corrects exposing of inline definitions #503)
2. Custom parameter types are now parsed when parameter objects are parsed. This is new. Previously all custom types were parsed at a later steps. Not sure if we need a models option in add_swagger_documentation method from now on, since it looks mostly like a workaround
3. changed links to custom types from "type": "TypeA" to "$ref": "#/definitions/TypeA"

[JanStevens]

One question, why is the length set to 42? Is this somewhere in the json schema spec (or swagger spec)?

[serggl]

great question, @JanStevens ! the answer is - no Idea :) this is a part of current code (https://github.com/ruby-grape/grape-swagger/pull/511/files#diff-7af39528837333c960830618fb6a52e9L297) which is not documented

[JanStevens]

Yes I know,

The reason why I'm asking is that our current project has different namespaces and internal and public apis. So our entities end up being AnimalFarm::Internal::CowEntity current code strips this all down to AnimalFarmInternal (not really useful).

My current fix is to define a entity_name class method that just returns the name of the class, that works ofcourse but isn't really handy.

[serggl]

Can someone from maintainers bring some light here?

[dblock]

We have to ask @LeFnord, this was added in 054c54f it looks like.

[LeFnord]

Yeap, I did it, cause 42 is the answer of all 😉 …
but seriously, the intention of limiting it was only to have a readable definition name,
which could be very long in some cases, but it seems not long enough …

will create a PR tonight, which remove the limit, ok?

[JanStevens]

Maybe also document the entity_name option? By default I expect it to be class.name and if I want it differently I start adding entity_names to my entities

[LeFnord]

one night later … #515 removes the limit

@serggl … can you rebase your PR …

[serggl]

@LeFnord sure I can. Right after you guys merge #515?

[LeFnord]

thanks @serggl … good job 😄