* Updated SDK and NDK to Android 5:
android-sdk_r24.0.2-macosx.zip
android-ndk-r10d-darwin-x86_64.bin
* Updated build-toolchain to build both ARM
and ARM64 toolchains.
* Added ARMv8-a architecture (64-bit) to all
core builds.
* Patched "Page Size" issue in boost_1_57_0.
* Added new cross-platform boost/build-boost script.
* Added new LINK_MODE var (static|shared) that is
used by Boost, PolarSSL, and OpenSSL (Linux) builds.
* More DEP_DIR flexibility:
(a) DEP_DIR can be defined prior to call of build-all scripts.
(b) On Linux, vars-linux script will not override DEP_DIR.
for different ARM platforms:
1. armeabi
2. armeabi-v7a
Android build script will package both versions of libovpncli.so
in the .apk, where the correct version should be automatically
chosen by Android on install.
