Implement BigDecimal approximations of pi and e.
Implement BigDecimal approximations of pi and e.

This is a work-in-progress. Currently we won't win any awards but at
least we'll be able to support the precisions that most people will
be intersted in.

We still need better precision for all the other methods in Trig but
at least this is a start.

non/spire,siddhartha-gadgil/spire,woparry/spire,rklaehn/spire,adampingel/spire,tixxit/spire,kevinmeredith/spire,codeaudit/spire,non/spire,adampingel/spire,rklaehn/spire,JackSullivan/spire,JackSullivan/spire,AlecZorab/spire,codeaudit/spire,guersam/spire,kevinmeredith/spire,AlecZorab/spire,siddhartha-gadgil/spire,guersam/spire,woparry/spire,tixxit/spire