feat: add support for git+ssh repo urls

[RasPhilCo]

supersedes #74

[salesforce-cla]

Thanks for the contribution! Unfortunately we can't verify the commit author(s): Boshko Knezevic <b***@b***.i***.s***.com>. One possible solution is to add that email to your GitHub account. Alternatively you can change your commits to another email and force push the change. After getting your commits associated with your GitHub account, sign the Salesforce.com Contributor License Agreement and this Pull Request will be revalidated.

[codecov]

Codecov Report

Merging #103 into master will not change coverage.
The diff coverage is 0.00%.

@@          Coverage Diff           @@
##           master    #103   +/-   ##
======================================
  Coverage    0.00%   0.00%           
======================================
  Files           5       5           
  Lines          93      95    +2     
  Branches       17      18    +1     
======================================
- Misses         93      95    +2     

Impacted Files	Coverage Δ
src/commands/plugins/install.ts	0.00% <0.00%> (ø)

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