Merge pull request ruslo#111 from ruslo/pr.cmake.3.7.1

CMake 3.7.1

Add gcc-4-8-pic toolchain

Update README.md

Update environment for MSVC + Ninja

Update MSVC variables according to Hunter

Add NDEBUG to release flags

Add '--tail' option

Add '--discard' option

Add toolchains: ios-nocodesign-{arm64,armv7}

build.py: add '--target'

Fix issue ruslo#45