Merge commit 'v1.2.3-41-gc4c6c905' into releases (mtheirs)

* commit 'v1.2.3-41-gc4c6c905': (40 commits)
  test splitting resources to put the largest subfolder into its own separate source file
  make simd testing catch NaN values also
  add test of simd implementations, small tweak to wb_shortcuts completion
  add -simd global option to wb_command, new volume label probability and cifti label to border commands, help info tweaks
  some tweaks and helpers for simd to prepare for adding option
  further tweak to cifti resample help
  add some help for template direction in cifti resample commands
  use sddot in cross correlation also
  update copyrights, extra stubs for compiling SIMD option code without testing SIMD support defines
  Speed up correlation computation using SIMD instructions
  make completion behave better for filenames given for string arguments (and for questionably named directories) by adding a trailing slash and no space to directories
  wb_shortcuts update
  typo in help info
  fix error messages for invalid columns in -cifti-merge
  small update to wb_shortcuts
  update wb_shortcuts, put wb_shortcuts initial switch completion into bash completion
  allow use of map names in -cifti-merge
  fix wrong help info
  update/simplify readme
  some help text improvements
  ...