Create procfs_utils.c; File missed from last commit; + remove warning from mm_memalign.c (how did this work before?)

Move sleep() and usleep() from sched/ to libc/unistd/.  These functions now are simple wrappers for nanosleep().  Remove sleep() and usleep() from system calls; add nanosleep() to system calls

Add board support infrastructure for the pcDuino board.  There is not much there on the initial checkin

MTD NAND: Check if block number is out of ragne at top of loop, not bottom, to avoid some bogus transfers

LM: Don't initialize .data if running in SRAM.  Global missing intialize type.  SAMA5 NAND: Fix for read nand in smaller chunks

NXFFS: When dumping the MTD content, don't abort on a read error.  For NAND, the read error probably just means that an uncorrectable ECC was encountered

NXFFS: First of many changes for NAND.  NAND reports read errors on ECC failures.  NXFFS can't just give up in these cases and must treat read failures like bad blocks