Implement Q.algebraic assumptions for exp/log and trig functions

    see 7c99ac8b6be9aecb and 1c1f7e38dbca9869e9b
correct path to ask_update.py in docstring
Add facts: Q.rational => Q.algebraic and Q.algebraic => Q.complex (issue 2019)
AskAlgebraicHandler.Number should't return False, it's wrong!

    Instead implement Float method and return True for one (just as for
    rationals).
Implement Infinity and NegativeInfinity methods for AskAlgebraicHandler
Add Pi, Exp1, GoldenRatio, ComplexInfinity mathods for AskAlgebraicHandler
Implement Q.rational assumptions for exp/log and trig functions

    just as for Q.algebraic