Improvements for jwt

[kkalisz]

Hello, this PR adds following improvements:

• proper serialization of SecurityModel in case of bearer ( empty scopes)
• skip "name" field when serializing SecuritySchemeModel

It also adds bit flexibility during serialization:

• basic settings for serailization that includes possibility of serializing empty lists/maps
• possibility to override serialization for nested DataModel

closes #79 closes #68

[Wicpar]

Companion object default is redundant, as you have the default values already.

[kkalisz]

Thanks for feedback, I adjusted code.