Enable the QELEventGenerator to handle off-shell kinematics for the s…

…truck

nucleon. Allow the user to configure the calculation method used to arrive
at the binding energy. Update the Lewellyn-Smith and Nieves CCQE cross
section models to correctly apply the de Forest prescription, which
accounts for the off-shell struck nucleon by putting it back on shell and
using an effective value of the energy transfer.

config/QELEventGenerator.xml

@@ -13,6 +13,8 @@ MaxXSec-SafetyFactor     double  Yes   multiplies max xsec in rejection method
 MaxXSec-DiffTolerance    double  Yes   max allowed 200*(xsec-xsecmax)/(xsec+xsecmax) 999999
                                        if xsec>xsecmax
 Cache-MinEnergy          double  Yes   minimum energy for which max xsec is cached   1.00
+HitNucleonBindingMode    string  Yes   Method used to handle the binding energy of   UseNuclearModel
+                                       the struck nucleon
 
 -->
 
@@ -21,6 +23,9 @@ Cache-MinEnergy          double  Yes   minimum energy for which max xsec is cach
   <param_set name="Default"> 
     <param type="double" name="Cache-MinEnergy">        1.0       </param>
     <param type="alg"    name="NuclearModel">           genie::NuclearModelMap/Default            </param>
+    <param type="string" name="HitNucleonBindingMode"> UseNuclearModel </param>
+    <!-- <param type="string" name="HitNucleonBindingMode"> OnShell </param> -->
+    <!-- <param type="string" name="HitNucleonBindingMode"> UseGroundStateRemnant </param> -->
   </param_set>
 
   <param_set name="CC-Default">