Change how JOINT inputs are specified in the cardfile

[lp208]

Its a bit annoying having to truck around multiple text files with a card when using JOINT input types.

The Luke+Callum standards consortium propose

sample sample_name TYPE:(file1.root,file2.root)

This is different to a multi-vector sample, like a ratio, which would still look like:

sample sample_name TYPE:file_numer.root;file_denom.root

Notice the different delimiter, which may be confusing, but we can add checks on the read-in.

A ratio of JOINTS, e.g. NEUT numu+numubar PosPol? MiniBooNE ratio would look like:

sample sample_name NEUT:(numer_numu_fhc.root,numer_numubar_fhc.root);(denom_numu_fhc.root,denom_numubar_fhc.root)

in this way 'JOINT' becomes an internal word, which I also think is good becuase, to me, it isn't declarative enough for what it does, 'composite file' or whatever could be a better documentation heading.

[Clarence Wret]

Milestone renamed