Release GCC ARM Embedded 4.9 update 2

Written for GNU Arm Embedded Toolchain by Thomas Preud'homme on 2015-06-23

The 4.9 2015q2 update release is ready at:
* https://launchpad.net/gcc-arm-embedded/4.9/4.9-2015-q2-update
* https://launchpad.net/~terry.guo/+archive/gcc-arm-embedded.

Features:
* All GCC 4.9 features, plus latest mainline features
  - Cortex-M7 support
  - Small multiply support with options:
    . -mcpu=cortex-m1.small-multiply
    . -mcpu=cortex-m0.small-multiply
    . -mcpu=cortex-m0plus.small-multiply
* Dedicated multilib for Cortex-M7
  - cortex-m7
  - cortex-m7/fpu/fpv5-d16
  - cortex-m7/fpu/fpv5-sp-d16
  - cortex-m7/softfp/fpv5-d16
  - cortex-m7/softfp/fpv5-sp-d16
* Define aeabi_memcpy and aeabi_memcpy4 routines in newlib.
* Define aeabi_memmove, aeabi_memset and aeabi_memclr routines in newlib.
* Thumb-1 library optimizations.
* Additional code size optimizations.
* Add gdb python build (arm-none-eabi-gdb-py).
* Object file without attribute section can be linked with any
  others.
* The options -mapcs, -mapcs-frame, -mtpcs-frame and -mtpcs-leaf-frame
  will be deprecated in gcc 5.0, hence recommend to avoid them.

Important bugs fixed in 4.9 update 2 release:
* Updated some inline assembly code in Newlib to work with old targets
  https://www.sourceware.org/ml/newlib/2015/msg00386.html
* Avoid wastage caused by section size promotion
  https://answers.launchpad.net/gcc-arm-embedded/+question/262160
* Local register variables don't work correctly with inline asm operands
  https://bugs.launchpad.net/gcc-arm-embedded/+bug/1411655

Recommend to update to this release.