refs #8557 Two questions to 2 suspicious places of code

Two places found after code review which look like wrong. Questions to code were placed after //!!! mark
Merge branch 'master' into feature/8557_SNSvsISIS
Refs #8723 add LoadIsawSpectrum algorithm
Refs #8723 add LoadIsawSpectrum algorithm
Refs #8816 add predict peaks to SCD interface
Refs #8816 move predictPeaks after UB
Refs #8816 add argument
Refs #8816 make params visible
Commented out key in NeXus dictionary for POLDI

Key for proton monitor is not present in sample files, so it should not
be read.
Grouping workspaces created during POLDI analysis per sample
Merge remote-tracking branch 'upstream/master'
Changed name of POLDI WorkspaceGroup

Having the same name for the grouped workspaces as for the raw data
resulted in segmentation faults.
Refs #8830 convert bayes error notices to proper python exceptions.
Refs #8830 Fixed similar issues in IndirectCommon
Added code to represent POLDI's detector in an abstract way
Refs #8838 Prevent deletion of loaded workspaces.

This is consistent with the other routines in IDA.
Refs #8838 Disable option on plot when not available.
Added license blocks to header files
Refs #8816 fix dspacing params input
Added centralElement to Detector