fs.readFile returns 'undefined' if file is not found. Also make readdir return undefined on failure (fix #229)
new FatFS library
Remove disk_timerproc in SD card implementation
Merge branch 'master' into new_fatfs
Upgrade fatfs to R0.10a
Tweak jsinteractive.c to help reduce code size
Finally added Long filename support for FatFS (fix #78)