feat: add flag to init cmd to specify output file path

[skoenig]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #344

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

Additional documentation e.g., design docs, usage docs, etc.:

[github-actions]

CLA Assistant Lite bot All contributors have signed the CLA ✍️ ✅

[skoenig]

I have read the CLA Document and I hereby sign the CLA

[coveralls]

Pull Request Test Coverage Report for Build 8411517684

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 15 of 17 (88.24%) changed or added relevant lines in 2 files are covered.
• 3 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.1%) to 59.18%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/cmd/init/options.go	6	8	75.0%

Files with Coverage Reduction	New Missed Lines	%
pkg/engine/operation/parser/parser.go	3	79.27%

Totals
Change from base Build 8409888263:	0.1%
Covered Lines:	7333
Relevant Lines:	12391

---

💛 - Coveralls

[liu-hm19]

lgtm