Fixed the ST_ConvexHull bug, added ST_Intersection function and turned off the exception in ST_Transform

[jiayuasu]

This PR will fix the following issue:

1. fix ST_ConvexHull bug: Issue ST_ConvexHull should accept any type of geometry as an input #188
2. add a new function called ST_Intersection which returns the geometrical intersection of two geometries: Issue Add a new type of spatial join query that returns the intersections directly #110
3. allow the user to add one more parameter in ST_Transform to turn off the exception in ST_Transform to bypass "Bursa wolf" error: Issue with coordinates when reading shapefile #185
   ST_Transform (A:geometry, SourceCRS:string, TargetCRS:string, [Optional]UseLongitudeLatitudeOrder:Boolean, [Optional]IgnoreException:Boolean)