Extend GroupDetectors to read alternative grouping format

[Anders Markvardsen]

<detector-grouping instrument="">

<group name="fwd"> <ids val="1-16,19, 20"/> <group/> <group name="fwd"> <ids val="21-36, 39, 40"/> <group/>

<pair name="long">

<forward-group name="fwd"/> <backward-group name="bwd"/> <alpha val=""/>

</pair>

</detector-grouping>

[Anders Markvardsen]

(In [5379]) Extend GroupDetectors to also allow grouping to be read from following format

<detector-grouping instrument="MUSR">

<group name="fwd"> <ids val="1-32"/> </group> <group name="bwd"> <ids val="33-64"/> </group>

</detector-grouping>

Refs #1423

[Anders Markvardsen]

(In [5386]) Ups forgot to add 1st example for xml grouping file used in test. Refs #1423

[Anders Markvardsen]

(In [5389]) To get GroupDetector test to pass on win64. Refs #1423

[Anders Markvardsen]

(In [5391]) Will this sort out broken Ikeda-Carpenter test caused unexpectably by previous commit to this ticket? Refs #1423.

[Nick Draper]

fill in missing resolution

[Peter Peterson]

This works correctly.

[Stuart Campbell]

This ticket has been transferred to github issue ​2270