Allows `installing` a package without pulling dependencies of that
package. This comes in handy when having multiple directories on
`JPATH`, which overlay each other.
Because dependencies may be already present at lesser ranked import
paths, it's not required to pull them, when only needing to bump a
single one.
Several code-hosters like GitLab allow to have subgroups. These were previously not suppported because we weren't able to tell if something was a subgroup or a subdir.
By letting users specify the `.git` part of the http string as well, this now work for all protocol, including https.
