NEW: JKQTMathText: \limits and \nolimits work as in LaTeX now (before it was simply removed and the functionality implemented for a fixed list of symbols)
remove/breaking: JKQTMathText: \v[a-zA-Z] and shorthand for \vec{a-zA-Z} was removed
improvement: improved typesetting of sub-/supercripts, especially for large math operators and braces
