feat: high level wrapper around Docker API

[oleksandr-nc]

Partitially related to the nextcloud/app_api#531

In this pull request we add a wrapper around Docker Commands for AppAPI for Nextcloud 32.

All the wrapper logic is written in Python, all the main commands for which complex regular expressions for access control were written are covered in this PR.

This is what remains to be done for the future (most likely it will be for Nextcloud 33 or 34 when we drop DockerDockerProxy support):

# docker system _ping
http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/_ping$ } METH_GET
# docker inspect image
http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/images/.*/json } METH_GET
# container inspect: GET containers/%s/json
http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/containers/nc_app_[a-zA-Z0-9_.-]+/json } METH_GET
# container inspect: GET containers/%s/logs 
http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/containers/nc_app_[a-zA-Z0-9_.-]+/logs } METH_GET
# image pulling
http-request allow if { path,url_dec -m reg -i ^(/v[\d\.]+)?/images/create } METH_POST

[kyteinsky]

works quite flawlessly, tested even with custom ssl certs. 🚀

[kyteinsky]

🚀