Fix Voice on Linux.

No such thing as -st/shutdown timeout on Vivox 2.x SDK
Attempted fox for PNG
Check for signing variables before even trying to sign

Also tabs to spaces and fix typo.
Sync stuff
CMake 3 Fixies from Alchemy
[RLVa] Escape potentially dirty strings before using them as regex in replace_all_regex

Fixes crashes
This changeset is welcome for use in LGPL viewers

Thanks to Ansariel Hiller for pointing this crash out.
Merge pull request #1 from singularity-viewer/master

Merge in updates from singularity master