Add drowning mechanic to players.

* Players can stay in liquids for 15 seconds before drowning.
* Drowning damage occurs every second.
* Sounds are played when taking drowning damage.
* Breath meter is shown on the HUD.
Update code style for conformity.
Add Idea mod files to gitignore
Use ISO date time at build.gradle
Updated file 'VERSION'

Copied from TerasologyLauncher
Merge PRs #647, #648, #649 from @mkalb - gradle/gitty stuff
Reduces film grain intensity a tad.
Fixes weird behavior of the sky during the night (half of the hemisphere was darkened).