Android : add build.xml for JNI layer

This will attempt to compile the JNI layer as an
Android library project for use with the Launcher
for Android.
Android : add pre-compile step to build native code

Before building the Java code, compile the native
code!
Readme.markdown : add build status links

Displays the status of the master and develop branch
from jenkins right in the Readme as it is rendered
on the main page of the repository on github.
Remove unneeded file
BUG 74: Added some more logging to help verify paths
Fixed issue related to JNI static jclass pointer initialisation (ERROR "accessed stale local reference"), observable in Android ICS+ (>= Ice Cream Sandwich 4.0) because of the new garbage collector which moves memory allocations.
This was needed on my KitKat device despite targetSDKVersion set to 11 in project properties (which should normally ensure JNI compatibility mode with post-4.0 garbage collection ... I'm not sure why the compatibility mode did not kick-in though, I observed this bug in both Dalvik and ART runtimes).
Future uses of the jni::Class wrapper (defined in jni_class.h) should be double-checked, to ensure that the initialisation macro from helpers.h is used to create the correct persistent jclass memory pointer! (behind the scenes: (jclass)env->NewGlobalRef(tmpPtr)).
Perhaps INIT_CLASS_RETVAL() should be called directly inside the jni::Class constructor that takes a string parameter (the class qualified name, used to lookup via end->FindClass()). This would make the API transparent to the JNI garbage collection subtleties?
Merge pull request #55 from datalogics-bhaugen/jenkins-build-android

Jenkins build android
Android build.xml : add post build step to build doc

Hooks into the build.xml in api-docs directory to
build the doxygen documentation for the version of
Readium SDK that was just built.
Merge branch 'build-android-doc-after-sdk' into develop
Merge pull request #63 from datalogics-bhaugen/add-build-status-to-readme

Add build status to readme
README.markdown : add jenkins build status for windows

Adds the status of the different windows configurations
that jenkins is now aware of, all are currently
failing.
Merge branch 'add-windows-build-status-to-readme' into develop
Fixed minor build warnings for ePub3.xcodeproj
Removed warning-causing dylib linking for ePub3-iOS target