Install new ewoks workflow for launching sxx_proc

Just before leaving ID29 this afternoon I discussed with Marcus and Shibom how to launch the ssx_proc (edna2) script which runs the 'autocryst' processing. I suggested to make a new simple BES workflow which only task would be to launch ssx_proc with a given set of parameters.

However, when returning to the office, Wout and I discussed this topic and we agreed that it would be be better to install this as a new ewoks29 workflow. It would then be launched from MXCuBE like the max sum projection workflow. Ping @denolf @broche