CpmUserConfiguration should be global, not specific to the install action

Currently, user configuration is only parsed for the `install` action. It should be global, as other actions could make use of it.

This implies parsing the configuration in the `main` function of `cpm`at `__init__.py`.

Start in __init__.py and inspect the cpm main function alongside the current configuration parsing used by the install action. Move the parsing scope so CpmUserConfiguration is available to all actions, then verify that configuration is parsed when running actions other than install.

Written by the indexing model from the issue text.