Implement MakeValid

[peterstace]

MakeValid is an operation that exists both in PostGIS and GEOS. It basically accepts an invalid geometry as input, and then "makes it valid" by returning a different geometry that is similar (but not identical!) to the original.

There will be a few steps to implement this in simplefeatures natively in Go:

• Get a good understanding of how MakeValid actually works in PostGIS and GEOS, i.e. what is a description of the actual algorithm? Right now, it seems a little big "magical".
• Implement MakeValid.