Fix build errors on Linux and OS X

[Daniel-Cortez]

What this PR does / why we need it:

Fixes build errors that originate from an incorrect declaration of an array of function pointers (initially I declared it as static const void (*opers[])(void) while I should have used static void (*const opers[])(void) - this was no problem for MSVC and MinGW, but caused errors when building for Linux and OS X with GCC/Clang). Also removed a few excess trailing whitespaces while I was at it.

Which issue(s) this PR fixes:

Fixes #

What kind of pull this is:

• [ ] A Bug Fix
• [ ] A New Feature
• [ ] Some repository meta (documentation, etc)
• [x] Other

Additional Documentation:

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity.

[Y-Less]

Merged locally.