CB-8190 Make plugman config/cache directory to be customizable via PLUGMAN_HOME (close #134)
CB-8114 Specify a cache-min-time for plugins (closes #133)
CB-8129 Adds 'npm run cover' command to generate tests coverage report (close #131)
Updates README with description of npm commands for this package
CB-8155 Do not fail plugin installation from git url with --link (close #129)

This is wrong when installing a local plugin with dependencies from git repositories.
CB-7803 Allow adding any platform on any host OS (close #126)
CB-7311 Fix tests on windows for iOS parser

Changing the tests to use forward slashes for iOS according to the
previous commit:
https://github.com/apache/cordova-lib/commit/fef0ee701581c7dafc55dda207f1ec17e21bd644
CB-8216 Resolve plugin paths relative to original CWD
CB-8217 Fix plugin add --link when plugin given as relative path
CB-8215 Improve error message when `<source-file>` is missing `target-dir` on android