Rails native view tags support

[sebyx07]

#598

[jonasjabari]

hey @sebyx07! Thanks for the PR! I like the idea! Two things:

• I would not recommend to put support for third party gems like SimpleForm and Kaminari into the core code of matestack-ui-core. There are too many gems out there deserving to be supported. I would love to see documentation on how to support gems like that within an application trough an easy to use API rather than having it baked into matestack-ui-core
  --> Rails view helper support would be an exception of this as Rails cannot be seen as a third party thing
• We need some specs covering this feature and some minor docs explaining it

Would you be able to adjust your PR towards my feedback and add specs and docs? You find some documentation about the specs workflow here: https://docs.matestack.io/matestack-ui-vuejs/contribute (that's the one for matestack-ui-vuejs, the one for matestack-ui-core is somehow missing. You can just ignore the yarn/js/vuejs things in this guide, the rest should work for core as well)

Happy to help and discuss further!