Add jumpers to memory unit

Not sure of it's real headers like:
SRAM-------X X--------FGPA

Or if it just hooks on like this:
SRAM--------O---------FPGA
            |
            |
            X

            X
            |
            |

We need to check this out.
Make sure we have jumpers

Now we do have this:
    SRAM----------X X---------FPGA
Merge pull request #31 from dmpro2014/sram-head

Add jumpers to memory unit