Move all scripts to usr/lib/ndc/scripts
Move Python script to usr/lib/ndc/modules
Add shell script which wraps execution of `ndc`
Add `modules` dir to split script into moudles

Ignore compiled Python files under this directory.
Perform major split: single file into modules

- Single Python file is now split into modules.
- Fix multiple spelling errors.
Merge branch 'modules' - initial split of script