added irf.datatypes to explain typical datatypes
c_caa_cef_var_get accepts several variable request as cell array
added irf.datatypes - a help routine for different data types used in irfu-matlab
caa_get_dataset_name() to derive dataset name from variable name
c_caa_cef_var_get() can stream any variable from CAA
c_caa_var_get() if needed streams mat format from CAA + minor cleanup
c_caa_var_get() checks that Dataobject exists
c_pl_sc_orient() cleanup and fixing time definition