I2C slave working, with ELMA protocol on top. Submitting last changes + doc for I2C slave. Also updated order-record doc

Basic functionality with immunity to no input channel while in INV-TTL mode and documentation update.

Basic pulse repetition operational. Folder structure pretty much the same as before, but pulse repetition files exist in <pulse_generator> folder. <release> folder holds release version for the firmware.

Added old repeater boards' test. New project folder hierarchy started, as exemplified in old_rep_test/ folder.

I2C write seems to work fine, read is still a problem. Creating secondary branch to fix bicolor LEDs and switching to it.

Made changes to I2C protocol addressing and added Beagle software files and trigger LEDs vhdl for testing I2C communication. Switching branches to chipscope I2C comm.

Tracked back changes to V1 images. Commiting to create v1-hdl branch, prior to changing this branch for V2.