Log Message:
Changes 0.9.3:
* Avoid floating point overflow and underflow
* Do not use "Read Precision" in plot
* cos(x*pi*rad) equals 1 if x is even, not -1
* isodate(), localdate(), timestamp(), stamptodate() functions
* Fix show ending zeroes
* Fix prefixes with automatic simplification/factorization
* Approximate comparison
* ...and some more...