Mounting fixes and implementation of PWD with cross mounting points

[worseTyler]

1. Changes in inode and block allocation
2. Changes in how mount root works
3. PWD now checks for cross mounting points using the upward traversal method

NOTE: THIS MIGHT'VE BROKEN OTHER PARTS OF THE FILE SYSTEM
Use this code as guidelines for how to implement the mounting behavior

[Eastonco]

it's better than it was

[Eastonco]

gotta get @zjnett 's thoughts in here before we merge