This saves getting the FS and suffering the barrage of warnings
related to auto-closeable resources.

This means each test doesn't have to set it up and tear it down
manually (although only one actually did bother to tear it down :)).

Finish unit tests.

Change-Id: I5dba46bccd147283d8389dcc3d2a4aadf4d827be
Reviewed-on: http://gerrit.dmdirc.com/4002
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>

Make the ActionAliasMigrator use a Path, and add a basic
unit test. Need to make ConfigFile use paths to do anything
sensible.

Also refresh gradle libs in idea so JimFs shows up.

Change-Id: I0cb2692083d0fe117b91edce63d8417ddd74e288
Reviewed-on: http://gerrit.dmdirc.com/3999
Automatic-Compile: DMDirc Build Manager
Reviewed-by: Greg Holmes <greg@dmdirc.com>