cross 0.2.3

Zero setup cross compilation and cross testing
Documentation
FROM ubuntu:16.04
ARG DEBIAN_FRONTEND=noninteractive

COPY common.sh lib.sh /
RUN /common.sh

COPY cmake.sh /
RUN /cmake.sh

COPY xargo.sh /
RUN /xargo.sh

RUN apt-get update && apt-get install --assume-yes --no-install-recommends \
    g++-mips64el-linux-gnuabi64 \
    libc6-dev-mips64el-cross

COPY qemu.sh /
RUN /qemu.sh mips64el softmmu

COPY dropbear.sh /
RUN /dropbear.sh

COPY linux-image.sh /
RUN /linux-image.sh mips64el

COPY linux-runner /

ENV CARGO_TARGET_MIPS64EL_UNKNOWN_LINUX_GNUABI64_LINKER=mips64el-linux-gnuabi64-gcc \
    CARGO_TARGET_MIPS64EL_UNKNOWN_LINUX_GNUABI64_RUNNER="/linux-runner mips64el" \
    CC_mips64el_unknown_linux_gnuabi64=mips64el-linux-gnuabi64-gcc \
    CXX_mips64el_unknown_linux_gnuabi64=mips64el-linux-gnuabi64-g++ \
    BINDGEN_EXTRA_CLANG_ARGS_mips64el_unknown_linux_gnuabi64="--sysroot=/usr/mips64el-linux-gnuabi64" \
    QEMU_LD_PREFIX=/usr/mips64el-linux-gnuabi64 \
    RUST_TEST_THREADS=1 \
    PKG_CONFIG_PATH="/usr/lib/mips64el-linux-gnuabi64/pkgconfig/:${PKG_CONFIG_PATH}"