Can't edit an entry is it comes from included file

[pgiraud]

When using include statements in a configuration file, if an entry is set in the included file, pgtoolkit raises a ValueError if this entry is modified (value changed or commented out) within a with conf.edit() on context manager exit.

The commit a1cf3d710d94abaab9b6a30f0424c380ab80764c highlights the problem.