what should we do about duplicated transitions in external databases
There can be more than one type of radiative transition between some levels - an example being the 2s-1s transition in H-like species. Currently we stop when more than one transition is detected - see r5218.
to active the problem we must turn on H-like species in chianti - these are commented out by default since we use our own H and He like iso sequences. See closed ticket #206 to set up an example.