File-System-FAT

Implement a file system that uses a pseudo "FAT" on an mmapped buffer.
The functions to implement are

createFile
eraseFile
write (potentially extending the file boundaries)
read
seek
createDir
eraseDir
changeDir
listDir

The opening of a file should return a "FileHandle" that stores the position in a file.

In the InteractiveFS branch is a working remake of the command line in linux!