Craft Basic version 1.7.1 released

This is a small update, so I decided this will be v1.7.1 and not v1.8.

Did some cleaning up of the examples.

Added more examples ported from other languages.

Added a new function EXP()  for returning exponential value.

Documentation has been updated a bit.

New examples include:

rocket.bas

bombardment.bas

solarsystem.bas

snowflakes.bas

hexagondesign.bas

curve.bas