Add description and images for ST_BoundingCircle
Add description and image for ST_Expand
Update examples and images for ST_Expand
Add description and images for ST_Extrude
Add description for ST_MakeEnvelope
Add description, comparison and image for ST_MinimumRectangle
Update description and image for ST_MinimuRectangle and add comparison with ST_Envelope
Add description and images for ST_OctongonalEnvelope
Update the diffrente description
Update ST_OctogonalEnvelope and mini correction about other functions
Add description for ST_AddZ
Update description for ST_AddZ
Add description and image for ST_Densify
Add description for ST_Interpolate3DLine
Add description for ST_MultiplyZ
Add description for ST_Normalize
Add description and image for ST_RemoveHoles
Update description and add images for ST_RemovePoint
Update description for ST_RemovePoint
Update images for ST_RemovePoint