* Introduce patches with external kafka
* Fix pre-commit hooks
* Patch relay config file
* Documentation for patches stuff
* Provide more helpful information for Docker Compose Override file
* Fix grep command
* ref: rename to 'optional-modifications'
* chore(pre-commit): exclude .patch extension
* chore(pre-commit): escape backslash
* chore(pre-commit): put exclude field on hooks
* chore(pre-commit): put exclude field on top level
Based on https://pre-commit.com/#top_level-exclude
* chore(pre-commit): move to even more top level
