not quite there, but it seems like this should work for multicolor
flashing of the boss sprite when it is hit.
multicolored flash works, had to change the boss sprite to white and
black so that the shader could pick up the color (doesn't seem to work
on weird shades of color--stick to well-defined percentages to avoid
float problems; may be able to use Color32 to avoid this problem).

Think I could avoid using the BWBossFlash.mat by defining a material in
the BigBaddieController.cs script.  Not sure whether this is would be
better or worse than the approach involving the making a material in
the Editor.  It may allow for better tracking for git...
Sleep function works globally.  It's called when the PC is knocked
back.
more cowbell
refactor to use Random.value, which achieves the same purpose.
refactor to take care of the material stuff in code rather than the editor
update the prefab and the scene for the refactored material from 2062c32
switch to Color32 to avoid some RGB headaches
First pass at getting screenshake working.  adds a PlayShake method to
the ScreenShaker script attached to the main camera in Levels 01 and
02.  See BigBaddieController to see how it's used.
document the PlayShake function
Make an attempt at Perlin Noise, but I like random from 1cf8a82 better.
Revert "Make an attempt at Perlin Noise, but I like random from 1cf8a82 better."

This reverts commit 8887424800c28fe05bd0637cddb2372fa3d8426c.
added exp popup
refactor so ExpPopup.cs handles its own text string.
made a dead fish prefab
Merge branch 'master' of https://github.com/zerosalife/okeanos