Add back non-WebGL ocean overlay

[joshlory]

Resurrect the changes in PR #529 to draw the underwater overlay without the WebGL shader.

Not clear yet if the shader is causing issues on low-end Chromebooks, but creating this as a WIP PR in case we need it.

[codecov[bot]]

Codecov Report

Merging #558 into master will increase coverage by 0.02%. The diff coverage is 89.47%.

@@            Coverage Diff             @@
##           master     #558      +/-   ##
==========================================
+ Coverage    75.8%   75.83%   +0.02%     
==========================================
  Files          43       43              
  Lines        5378     5396      +18     
==========================================
+ Hits         4077     4092      +15     
- Misses       1301     1304       +3

Impacted Files	Coverage Δ
src/js/game/LevelMVC/LevelView.js	84.75% <89.47%> (-0.03%)	:arrow_down:

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