No longer dump memory elementSize

Previously the Core CrashCatcher module would dump the startAddress,
endAddress, and elementSize previous to dumping the actual contents of
a memory region.  It turns out that the elementSize isn't really all
that useful.  Everything is dumped as bytes in little-endian order
anyway.
Add HexDump module

This module provides an implementation of the core CrashDump callbacks
to generate a text based hexadecimal crash dump.  The user just needs
to provide CrashCatcher_GetMemoryRegions(), CrashCatcher_getc, and
CrashCatcher_putc() implementations.
Build libCrashCatcher_HexDump* libs

Now building ARMv6-M and ARMv7-M versions of the CrashCatcher libs with
HexDump functionality provided.