[g2p_ana] Beam Current Added to MySQL

[Ryan Zielinski]

Hi everyone,

I wanted to let everyone know that I've added the beam current for each run to the AnaInfo tables on the g2p MySQL. I've also updated the function calls, so you can access the information from a ROOT/C++ script. The function call is get_my_current(run#) and returns a double/float. The current values were calculated by Pengjia and have a beam trip cut of 2nA. 

Cheers,
Ryan