There is no documentation for some rules

[MansurAliKoroglu]

Description

Four of the rules has no documentation.

Steps to Reproduce

1. Visit the links:

• https://github.com/xjamundx/eslint-plugin-promise/blob/HEAD/docs/rules/no-promise-in-callback.md
• https://github.com/xjamundx/eslint-plugin-promise/blob/HEAD/docs/rules/no-callback-in-promise.md
• https://github.com/xjamundx/eslint-plugin-promise/blob/HEAD/docs/rules/avoid-new.md
• https://github.com/xjamundx/eslint-plugin-promise/blob/HEAD/docs/rules/prefer-await-to-callbacks.md

[xjamundx]

Partially addressed in #215

[DerZyklop]

Related discussion about the reasons for avoid-new: #111

[DamienCassou]

I agree that rules should be documented.