Making the program more modular.

* Datablock has variable length fields and constants
which can be modified. Hence it is easier now to extend
it to any simulation.
removed structure.cpp from git
Moved the kernels to kernels.cu

Moved the kernels. Made some formatting changes.
fixed memory leak in datablock
Moved the constants to a different file.

FIXME: Still have to take care of the DIM
new constants file
0 changed to TE_SIMULATION
moving to coefficients started
Moved to coefficients completely in kernels

Saved 200 ms during the update