OS test:  Add a test of POSIX timers using SIGEV_THREAD.  Also, clean up many warnings with building on a PC with 64-bit addresses

apps/examples/pca9635:  Add a simple test of PCA9635PW PWM LED driver.  From Alan Carvalho de Assis.

apps/netutils/ping:  This is an unfinished implementation of ping/ping6 using raw packets.  Not yet even hooked into the build and configuration systems

netutils/telnetd:  No longer calls OS interfade telnet_driver.  Now creates Telnet sessions by open a new factory device at /dev/telnet and then using ioctl calls to create the session character drivers at /dev/telnetN.

NSH DD command:  Use nsh_freefullpath() instead of free().  Actually, these are the so this does not fix bug.  It is just needed for symmetry.

apps/nshlib:  The 'ps' command now uses /proc/(pid)/ to obtain task status information.  A consequence of this is that you cannot use the 'ps' command if the procfs is not enabled and mounted at /proc.

apps/nshlib:  The I/O buffer, g_iobuffer, should not be a global buffer.  That will not work in an environment where there are multiple NSH sessions.  The I/O buffer must, instead, be a part part of the session-specific data defined in nsh_console.h # Please enter the commit message for your changes. Lines starting # with '#' will be ignored, and an empty message aborts the commit.

apps/nshlib:  Add a new NSH losmart command.  losmart setups up a loop device for the smart MTD driver similar to losetup but with different syntax.  From Ket Petit.

nshlib:  Move trim_dir() and foreach_direntry() from nsh_fscmds.c to nsh_fsutils.c as nsh_trimdir() and nsh_foreach_direntry(), respectively

nshlib: Use CONFIG_NSH_PROC_MOUNTPOINT instead of literal /proc; Move readfile() from nsh_proccmds.c to nsh_fsutils.c as nsh_readfile()

apps/nshlib: Remove all references to internal OS interface netdev_foreach().  Logic in ifconfig, ifup, and ifown now use the procfs file system to examine networking status.