closed #3990: ParticleSystemQuad::setTotalParticles() can't set a value larger than the initialized value.
closed #3990: Adds test case for issue 3990.
Adds 'ParticleSystemQuad::updateTexCoords' method.
issue #3990: setTotalParticles works as expected. _emissionRate has to be updated in setTotalParticles.
Merge pull request #5328 from dumganhar/iss3990-particle

closed #3990: ParticleSystemQuad::setTotalParticles() can't set a value larger than the initialized value.