feat: contract long working directory paths
feat: contract long working directory paths

When the user surpasses (by default) 4 directories in depth, contrail
will remove the directories in the middle and only show the first and
last 2, separated by "..."

So a long directory name like:
"~/super/long/directory/name/that/is/long" becomes:
"~/super/.../is/long"

Of course, the user can configure the maximum depth by specifying
`max_depth` under `[modules.directory]`.

Afulton11/contrail