Dynamically allocate working buffers instead.

Closes #3

Sometimes, for whatever reason, native code fails to get installed
on some small percentage of Android devices.  In contrast to every
other device, on LG devices, the call to System.loadLibrary
 *succeeds*, and then the individual native calls throw exceptions.

This change allows the degredation path to work correctly on LG.

actually need to treat it as a source set.

Use separate modules in order to build both a java as well as an
android artifact, with separate and shared test cases.

1) Mavenize the project.

2) Create an interface that represents a generic Curve25519 Provider.

3) Wrap the Java port into a Java provider.

4) Wrap the NDK port into a Native provider.

5) Move Trevor's tests into JUnit format.

6) Copy the libaxolotl NDK ECC implementation tests here.