[TASK] Refactor cache command to cache service
[TASK] Add important TODO items for cache command
[!!!][FEATURE] Make cache:flush command force flush caches

This is done with moving the flush command to the
compile time sequence.

In doing so it is not possible any more to flush
caches by groups using cache:flush

Instead cache:flushgroups must be used.

Additionally the flush by tags command is now: cache:flushtags