Added new tests in AlertValidatorTests
Event Code Validator
Event Codes Validator
Headline Validator
Parameters Validator
Language Validator
Digest Validator
Geocodes Validator
MimeType Validator
WGS84 Validator
Circle Validator
Polygon Validator
Repaired Language Validator
Made topLevelMediaType static & simplified
Simplified Code
Reorganised Circle Validator
Fixes #53
Fixes Name Problems in Latitude/Longitude
Merged
Circles Validators now return WGS84Error instead of CircleError