Limit to length of filesystem path into which you clone Habitat

[nickwesselman]

Describe the bug
Due to Windows filesystem length limitations, Unicorn/Rainbow has a default limit of 110 characters on a serialization folder path. Habitat has serialization folders as long as 48 characters (relative to the repo root), meaning that Habitat cannot be cloned into a path longer than 62 characters.

To Reproduce
Clone Habitat into a path longer than 62 characters and attempt to sync.

Expected behavior
Documentation should loudly state this limitation. We could potentially also shorten the folder or configuration names to allow a longer path.