License management (Alternative to `coho audit-license-headers` and `coho check-license`)

[janpio]

https://github.com/apache/cordova-coho/blob/master/docs/plugins-release-process.md#license-check

https://github.com/apache/cordova-coho/blob/e838cc0f821593a3042f22bec681e5809ee7d33b/src/main.js#L71-L79 https://github.com/apache/cordova-coho/blob/master/src/audit-license-headers.js https://github.com/apache/cordova-coho/blob/master/src/check-license.js https://github.com/apache/cordova-coho/blob/master/src/validLicenses.json https://github.com/apache/cordova-coho/blob/master/src/knownIssues.json