Expose scope's bin directory to action commands

[noizwaves]

Problem

To better support shared configurations, it would be useful to access the scope configuration directory from within a check or fix command. This would allow for the loading of shared scripts that implement standard library type functionality.

For example, in an application's .scope/bin/some-fix.sh:

. "${SCOPE_BIN_DIR}/../etc/scope/stdlib.sh"

usage "some-fix"
custom_function_2 

Solution

Use std::env::current_exe() to make the bin directory available as SCOPE_BIN_DIR.

TODO

• [x] tests