boost: raise deployment target defaults from 5.0 to 7.0
boost: enable arm64 and x86_64 builds; remove armv6 build
boost: add patches to make 1.55.0 build with clang 3.4 and later
Merge branch 'fuego-on-ios' into fuego-for-littlego
re-enable x86_64 architecture for Fuego simulator build
Merge branch 'fuego-on-ios' into fuego-for-littlego