feat: 'kpm add' supports local path.

[zong-zhe]

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

fix #133

2. What is the scope of this PR (e.g. component or file name):

pkg/cmd/cmd_add.go

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[coveralls]

Pull Request Test Coverage Report for Build 5721950071

• 31 of 141 (21.99%) changed or added relevant lines in 6 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.1%) to 39.835%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/oci/oci.go	0	1	0.0%
pkg/opt/opt.go	0	10	0.0%
pkg/package/package.go	17	28	60.71%
pkg/package/modfile.go	6	26	23.08%
pkg/package/toml.go	8	35	22.86%
pkg/cmd/cmd_add.go	0	41	0.0%

Totals
Change from base Build 5689457368:	0.1%
Covered Lines:	1011
Relevant Lines:	2538

---

💛 - Coveralls

[Peefy]

LGTM