Merge pull request #45 from dinau/master

Fixed: The issue of interrupt vector remapping for GCC_ARM LPC1114
Added toolchain hooks and support for LPC4088_EA binary generation

A new hooks mechanism (hooks.py) allows various targets to customize
part(s) of the build process. This was implemented to allow generation of
custom binary images for the EA LPC4088 target, but it should be generic
enough to allow other such customizations in the future. For now, only the
'binary' step is hooked in toolchains/arm.py.
Merge remote-tracking branch 'github/master'