[Clas_cascades] Lambda1520 update

[Zhiwen Zhao]

Hi, folks

1. some slides with differential cross section comparison to g11 result
2. draft of analysis note
http://www.jlab.org/Hall-B/secure/eg3/zwzhao/analysisnote_Lambda1520_v2.pdf
There are still thing I am working on, particularly, Phi(1020) cut and 
systematics.
To the yield extraction plots, looking into my thesis on the wiki, I 
didn't include these in the note.
3. See the missing mom cut, see the note section 4.8
Here is a plot with linear scale on the neutron channel
http://clasweb.jlab.org/rungroups/eg3/wiki/index.php/PrtK0Km_theta1540#Missing_Mom_of_Proton 

The cut at 0.2GeV remove 11% and 8% of Lambda1520 total yield from the 
proton and neutron channel

Thanks

Zhiwen