Function aliases for math number rounding.

[cmarcelo]

Add function aliases in source:misc/S29_round.pl. Will increase Google juice.

Skill: know how to make a p6 function alias

FIXME native english: 'toward' or 'towards'? the article uses both...

    round_half_up_symmetric => round_matlab
    round_half_up_asymmetric => round_java
    round_half_even => round_bankers
    round_half_even => round_vb
    round_random => round_stochastic
    round_ceiling => round_towards_positive_infinity
    round_floor => round_towards_negative_infinity
    round_toward_zero => round_fix