DOC clarify a comment
TEST Safer testing

Check for errors in cover calls
FUNCT run the tests with and without cover

The code paths vary a bit in both cases
BUGFIX typo in a function call
FUNCT restore the code for covered modules

Use the cover compiled code stored in the cover data base instead of reloading
the code from the beam file
RESTRUCT Use moka_mod_utils:restore_module/2

Instead of using the soon-to-be-deleted moka_cover_utils module
RESTRUCT Get rid of an unused module

Was created for a different strategy, we added the cover code to moka_mod_utils
as the new strategy fits there
TEST raise the timeout for the fsm test

It seems now that cover is preserved it is more likely to take more than 10
seconds in an i5.

I need to investigate more but it can be due to excessive bumping of the cover
db or because is harder to reload cover instrumented code ...