add v1 of bs2st with b+ to ppipipiX

Adds full DST lines for Bs2st -> K- (B+ -> p3pi X), finding X=Lambda_c without reconstructing its decay products. Includes swapped charge lines for background studies. The individual rates are at the limit during the last full test (corresponding to committed version):

StrippingReport                                                INFO Event 100000, Good event 100000
 |                                              *Decision name*|*Rate,%*|*Accepted*| *Mult*|*ms/evt*|
 |_StrippingGlobal_                                            |  0.1530|       153|       |   7.158|
 |_StrippingSequenceStreamCharmCompleteEvent_                  |  0.1530|       153|       |   7.143|
 |!StrippingBs2st2pKpipipiLine                                 |  0.0390|        39|  1.872|   5.690|
 |!StrippingBs2st2pKpipipiSSLine                               |  0.0590|        59|  2.678|   0.034|
 |!StrippingBs2st2pKpipipiWSLine                               |  0.0540|        54|  2.074|   0.113|
 |!StrippingBs2st2pKpipipiWSSSLine                             |  0.0660|        66|  2.424|   0.029|
 |!StrippingBs2st2pKpipipiLine_TIMING                          |  0.0390|        39|  1.872|   0.029|
 |!StrippingBs2st2pKpipipiSSLine_TIMING                        |  0.0590|        59|  2.678|   0.028|
 |!StrippingBs2st2pKpipipiWSLine_TIMING                        |  0.0540|        54|  2.074|   0.027|
 |!StrippingBs2st2pKpipipiWSSSLine_TIMING                      |  0.0660|        66|  2.424|   0.027|

but the combined rate is 0.15 for four lines due to overlap. Further cuts will remove some signal; candidates in the config dictionary are:

• Km_MinPperp > 70 and Km_MaxPperp < 315 to drop to 29/55/49/56 events
• Km_MinPT > 600 to get 34/49/45/58
• B_MaxVtxChi2 < 3 to get 35/53/48/60
• all of the above gives 22/41/36/44

A complete test with updated cuts is still in progress. As best I can tell the multiplicity are true combinatorics with different tracks.