Factorize 'branch' function to limit the try/except scope
Make the match_or_raise pattern appear
Creation and usage of _match_or_raise
Usage of _values_to_int and _match_or_raise in several places.

Not finished.
Creation and usage of _rstriponce
More usage of the _match_or_raise pattern
'change' restructured
'client' restructured to limit the try/catch scope
'label' restructured to limit the try/catch scope
Using more _match_or_raise pattern
Created and started using the _run_and_process function
Added comment to explain why 'where' is not parsed by regular expressions.
Use _run_and_process in some of the commands
Usage of _run_and_process in 'branches'
Usage of _run_and_process in 'branch'
Usage of _run_and_process in 'flush'
Usage of _run_and_process in 'labels'
Usage of _run_and_process in 'label'
Usage of _run_and_process in 'clients'
Usage of _run_and_process in 'client'