cpu/examples/sys/drivers: reduce scope of variables
force travis to use 4-* (4-8-2014q2-0precise9 or newer) gcc-arm-none-eabi due to a bug not
installing the c++ headers when installing the stock cross-compiler
boards: msba2-common tools: reduce scope
dist: linux-border_router: reduce scope
Merge pull request #1657 from N8Fear/scope

lint: reduce scope (2)
Merge pull request #1605 from BytesGalore/fix_travis_arm_none_eabi_cpp

travis: force specific compiler branch to install the c++ headers