x86:  fix 'Error: .size expression for idle_stack does not evaluate to a constant' bug from Matt Campbell

Assembler changes with the gcc-47 distribution from ARM mean that we need to be explicit about branch one or more of the wide branch opcodes results in bad table branching.  From Mike Smith

configs/efm32-dk3650: Support for Energy Micro's development kit for the Leopard Gecko MCU.  From Richard Cochran

arch/arm/src/Makefile: dependency directory list is now computed from the VPATH.  From Richard Cochran

Config.mk: If WINTOOL is set, COMPILE definition should convert path generated by Cygwin make to a proper Windows path.  From Richard Cochran (2014-1-23).

NSH:  Add a break command; if-then-else and looping behavior can not be configured out of the build for small systems that need minimal scripting capability

NSH:  Loosen up if-then-else-fi syntx so that a command can be on the same line as the 'then' and 'else' tokens.  This allows, as an example, 'if true; then echo true; else echo false; fi' which is much more bash-like