Include crossbuilt libraries in android build

Android JNI interface requires usage of ndk-build. The added files use the
crossbuilt static libraries and makes them available for the JNI files.
Appropriate script is appended to build.sh so as to ndk-build and install the
application to android and start its Main activity.

Signed-off-by: Venkatesh Shukla <venkatesh.shukla.eee11@iitbhu.ac.in>
Added required submodules

The project requires lbdivecomputer, libusb and libftdi as its dependencies.
These libraries need special tweaking to work on android. These are provided in
my forked repository.

Signed-off-by: Venkatesh Shukla <venkatesh.shukla.eee11@iitbhu.ac.in>
Initial Testing of subsurface source files

A very naive attempt at compilation of subsurface files essential for making a
library. These files should be referenced by making a subsurface submodule.
Still there are loads of error shown on the screen.
Also, for building dependencies, appropriate commands are written in bashrc

Signed-off-by: Venkatesh Shukla <venkatesh.shukla.eee11@iitbhu.ac.in>