refs #8571. Fix merge conflict.
Merge remote-tracking branch 'origin/feature/8569_instrument_view_starting_point'
Merge remote-tracking branch 'origin/feature/7606_fitparam'
Merge remote-tracking branch 'origin/feature/8580_plot_tube_against_oop_angle'
Merge remote-tracking branch 'origin/bugfix/8346_OSIRIS_diff_merging'
Merge remote-tracking branch 'origin/feature/8176_indirect_trans_alg'
Re #8666. Switch to a read-write lock instead of a simple mutex.

See if this improves the timings.
Merge branch 'feature/8666_getfunctionnames_performance' into develop