Begin support for Sd cards

Summary:
Added support for M20 - M30 including unit testing.
AtCore can now do some basic SD card commands.

• Mount/UnMOunt (not on the gui)
• List files on the card with clean names.
• Delete most files on the card. Had issues deleting a file named "this is a file with spaces in the name" from my card
• Print from the sd card. stock print, pause, stop , resume have been updated to suport sd opperations.

TODO:

• SD card printing progress is not set up
• Detect when sd prints end
• Repetier Plugin
• Marlin Plugin
• Teacup Plugin (need to build Firmware)
• Aprinter Plugin (need to build Firmware)
• Sprinter Plugin (need to build Firmware)
• Smoothie Plugin (need testers No smothieboard, #reprap says its just like repetier for sd ops.)

Future Improvements:

• SD card prints when stoped do not currently return the current line or byte. This can be stored and used to resume prints later on .
• Making new files. This is kinda weird since you open a file with M28 then all codes sent after this are written to the file until M29 is sent to end the writing.

Test Plan:
This Tested. Built, Small jobs started and manipulated a few finished. It will need more testing on marlin marlins is kind of weird.

Tested on:

• Repetier
• Marlin

Reviewers: laysrodrigues, patrickelectric, tcanabrava

Reviewed By: laysrodrigues, patrickelectric

Subscribers: Atelier: AtCore

Differential Revision: https://phabricator.kde.org/D10299