feat(install): git submodule handling

[Tychus]

Description

Husky so far is unable to handle install on submodules. This PR attempts to solve that by adding:

1. IgnoreSubmodule option to both attach and install which will either prevent the whole target from being executed (same as Husku = 1) or in the case of install make it break the installation process if it detects it's a submodule.
2. When IgnoreSubdmoule is not specified the install command will then attach the husky hooks to the correct .git directory which is not .git in the case of submodules.

See more details here #69

Fixes issue (#69)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• I have performed a self-review of my code
• I have added tests that prove my fix is effective or that my feature works
• I have made corresponding changes to the documentation
• I have commented my code, particularly in hard-to-understand areas
• New and existing unit tests pass locally with my changes
• I did test corresponding changes on Windows
• I did test corresponding changes on Linux
• I did test corresponding changes on Mac

[alirezanet]

Nice 💐
LGTM 🚀

[alirezanet]

Hi @Tychus,
I merged the PR since this is not a blocker to this feature ... but if you have time please add corresponding information to the documentations also, would make it easier for others to use your feature.
and thank you for your contribution.