New deformvertexes mode + r_water optimization

New shader keyword: deformVertexes roundwave <radius> <wavelen>
<radiusexponent> <centerx> <centery> <wavefunc> <base> <amplitude>
<phase> <freq> . Which makes round waves coming from center point.
Radius is max radius of roundwave. Wavelen is length of wave at the
start. Exponent is a power function, it makes wave longer with the
distance from center point. Center offset are offset from entity center
(or from world origin for worldspawn surfaces).
r_water_lowquality: now disables deformvertexes in reflection/refractino
rendering
r_water_skipblackplanes: new cvar that allows skipping of black planes
rendering (if you want water without reflection or refraction, just set
color to 0 0 0).

deformVertexes roundwave 180 18 3  74  74 0 sin 0 1.00 0.0 1.2