Try to speedup painting
This is a follow up on the MR to fix the braille characters. I'v realized that we are doing too many multiplications (terminalDisplay->loc()) and because the calls where done to lambdas it's impossible to test them.
By caching the Character accessed by terminalDisplay->loc() we eliminate at least ~20 multiplications per cell. And the resulting code is more testable. Tests not done - too sleepy for that now.