specifies a ":" separated (on Windows ";" separated) list
of Git object directories which can be used to search for Git
objects. New objects will not be written to these directories.
++
+ Entries that begin with `"` (double-quote) will be interpreted
+ as C-style quoted paths, removing leading and trailing
+ double-quotes and respecting backslash escapes. E.g., the value
+ `"path-with-\"-and-:-in-it":vanilla-path` has two paths:
+ `path-with-"-and-:-in-it` and `vanilla-path`.
`GIT_DIR`::
If the `GIT_DIR` environment variable is set then it