Define proper and portable constants

[hollasch]

The current code base uses M_PI and MAXFLOAT. Both of these should be simple C++ constants defined somewhere. This may induce the need for a new common header (constants.h?).

Also note that MAXFLOAT, in addition to not being portable, also defines the maximum representable finite floating-point value. It should really be replaced with infinity (of the appropriate precision).

[ronaldfw]

@hollasch Mind if I take this? I will try to make all code compile and run on Windows/Linux/Mac and I think this is part of that.

I'll assign to myself, but please reassign if you have already started or want to work on this.

[hollasch]

Sweet — thanks Ronald!

[ronaldfw]

Fixed on the future branch.

[hollasch]

Now in the development branch.