* added/improved global chroot support
* added RESPONSE_FILES flag to support optional response files (on linux the cmd param length is 2 megabytes). Default True
* added unified handling for archive and link response file (similar to includes)
* added COMPILE_C_AS_CPP flag to support compiling of c files as cpp. Default False
* added mbedToolchain.init() for post __init__ hooks
* added caching to mbedToolchain.need_update() to reduce IO hits
* added support to identify compiler warning/error column (supports ARMCC, GCC and IAR). Errors/warnings now report file@line,col
* added global TOOLCHAIN_PATHS which allows overriding/changing of the toolchain paths. Also simplified ARM-related paths
* added target.json to mbed library release (by @0xc0170)* migrated compile_worker() to utils.py for lightweight thread initialization
* improved run_cmd() performance by removing unnecessary check about the command being executed (should be checked once in the relevant toolchain instead)
* removed remnants of Goanna support (should be reimplemented as hooks to compile/link/archive instead)
* fixes for Python 2.7 compatibility (by @0xc0170)
* fixes for Exporters (by @0xc0170)
Mihail Stoyanov
Jimmy Brisson