Avoid calling pthread_join() to wait for USB MSC thread to terminate:  This does not work if the caller of usb_mscuninitialize() is in a different task group than the MSC thread.  From David Sidrane

Extend stack debug logic to include IDLE and interrupt stacks.  Also color the heap as well.  Based on suggestions from David Sidrane

Add an MTD device wrapper that can used to provide a /dev/config that can be used for retaining configuration data.  From Ken Pettit

arch/arm/src/stm32/stm32_usbdev.c: On a failure to bind the class driver, the driver reference was being nullified too soon.  This caused an exception in usbdev_reset() later.  The driver reference will be null
ified later usbdev_unregister when the caller gets the error.  From David Sidrane

sched/sched_releasetcb.c:  Fix an error handling case where a pthread start-up fails early, before the task type has been saved in the TCB.  It is safer to use the sched_releasetcb() task type argument instead of relying on the task type in the TCB to be valid.  Reported by David Sidrane

scanf() fixes from kfrolov: 1) sscanf() function hangs in the following example: sscanf(2, %u,%u,%u,%u, ...), 2) sscanf() returns incorrect number of parsed numbers if some arguments can't be parsed: sscanf(=2, %u,%u,%u,%u,...)==1 instead of 0, and 3) using of char* instead of const char* in vsscanf function leads to warnings from GCC.