Add -h alias for --help option

[jan25]

Add shortcut option for help to support pip-compile|sync -h

Changelog-friendly one-liner: Add -h alias for --help option

Contributor checklist

• Provided the tests for the changes.
• Gave a clear one-line description in the PR (that the maintainers can add to CHANGELOG.md on release).
• Assign the PR to an existing or new milestone for the target version (following Semantic Versioning).

[codecov]

Codecov Report

Merging #1163 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #1163   +/-   ##
=======================================
  Coverage   99.50%   99.50%           
=======================================
  Files          36       36           
  Lines        2839     2839           
  Branches      333      333           
=======================================
  Hits         2825     2825           
  Misses          8        8           
  Partials        6        6           

Impacted Files	Coverage Δ
piptools/scripts/compile.py	100.00% <100.00%> (ø)
piptools/scripts/sync.py	100.00% <100.00%> (ø)

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[atugushev]

Hello @jan25,

Thanks for your contribution! Looks good. I'd prefer to pass the dict directly to the command(). See the suggestions below. Let me know what you think.

[jan25]

@atugushev thanks for the review. I like your idea of passing dict value as named arg, so accepted suggestions.

[atugushev]

LGTM 👍

[atugushev]

@jan25

Nice first contribution! 🎉 Thanks!