more cleanup.
identified defects nosfs routines for getting free/used space
(added to known issues, low priority)
TODO:
address the known issues
(both are show stoppers for write operation)
Implement remaining HddDriver isr cases in this order:
list, write read
complete iProj 4
known issues:
nosfs.makeDirBlock doesn't handle file names too long
nosfs.makeFileBlock doesn't handle files that span blocks
defective functions in nosfs: get(Used/Free)(File/Fat)Blocks