Add coverity scan support to travis builds

any builds on the coverity_scan branch should now get scanned.
Fix syntax error.
Maybe fix errors?
Don't use matrix for static analysis to save our build quota
Merge pull request #967 from mc-server/master

Merging master to coverity_scan for scan
Merge pull request #968 from mc-server/master

Second attempt at scan
Merge pull request #970 from mc-server/master

Merge to coverity
Merge pull request #976 from mc-server/master

Coverity merge
Merge branch 'master' into coverity_scan

Conflicts:
	.travis.yml
Merge pull request #1081 from mc-server/master

scan
Merge pull request #1107 from mc-server/master

Coverity merge
Enderman attacks a player if he's looking at him.
Improved Enderman code
Replaced strange algebra with dot product.

10 degrees is a completely arbitary constant I pulled from nowhere. Feel free to adjust this value.