use TARGET_ARCH instead of hardcoded arch in paths

use $(TARGET_ARCH) inside Android.mk to include prebuilts and includes depending on the target architecture.
Merge pull request #5 from ph0b/patch-1

use TARGET_ARCH instead of hardcoded arch in paths
remove "ref" as sodium.h has changed
Merge branch 'master' of https://github.com/joshjdevl/kalium-jni
update for latest libsodium remove "_ref"
Added extended installation readme.
Markdown correction.
Merge pull request #7 from valls/master

Readme extended
Add crypto_aead_chacha20poly1305 support
Rename libtestjni.so to libkaliumjni.so
Merge pull request #10 from lann/rename-libtestjni

Rename libtestjni.so to libkaliumjni.so
Merge pull request #9 from lann/aead_chacha20poly1305

Add crypto_aead_chacha20poly1305 support
reference INSTALL.md and clean up readme
fix typo
shared object filename
Clarify compile.sh usage for different archs.
Add examples for different architectures
Merge pull request #11 from folex/master

Clarify compile.sh usage
Added missing VerifyKey getter to SigningKey class
Added architectures to Application.mk to ensure all shared objects build as expected