Remove incriminating evidence from the RA preview image

Addresses Scott's concern about the wrong explosion type on the sub pen.
Fix issues in 'intervention' mission

* Fix an InvalidOperationException due to querying traits on a dead
  actor (fixes #5530)
* remove a gap in the SAM belt that shouldn't be there
Merge pull request #5532 from obrakmann/random-fixes

Random fixes
Slackware 13.37 is way too old for us now
update Debian/Ubuntu and SUSE build dependencies
document Lua 5.1 for Windows
fixed syntax errors
complete the Gentoo dependencies via @cerebrum
/usr/bin/openra needs make install-linux-shortcuts
Check team members' health in Team.Do function
Remove now redundant Actor.IsDead checks from mission scripts
pacman does not exist on Ubuntu
update encrypted OAuth
Merge pull request #5537 from obrakmann/more-lua-crash-fixes

More lua crash fixes
Add Bountysource badge to README

Because you have some open bounties, we thought you might want to display this badge in your README!
Merge pull request #5548 from bountysource-support/patch-1

Add Bountysource badge to README
whitelist pkgtest branches
Merge pull request #5545 from Mailaender/travis-oauth

Tried to get Travis deployment under control
new OAuth new luck
Merge pull request #5554 from Mailaender/travis-openra-oauth

Updated the Travis CI OAuth token (again)