Aws-lambda-decorators

- Added group_errors flag to both extract and validate decorators. By setting this flag to True, all errors for all parameters will be grouped together and returned as a list of key/value objects, where the key is the name of the validated property, and the value is a list of all the errors found when validating that parameter.
- Regular Expression validators do a full match now instead of a search.

- Added Maximum Value validator
- Added Minimum Value validator

Examples have been moved to https://github.com/gridsmartercities/aws-lambda-decorators-examples, so new test.pypi releases can be tested against that repo easily.

- Added schema validator. Check out __`SchemaValidator`__ [here](https://github.com/gridsmartercities/aws-lambda-decorators/blob/0d8c354dfbea4994b76ab25fc2fe01ea5e9a4dbc/aws_lambda_decorators/validators.py)

Added cors decorator, which can add cors headers to the response of the decorated function (lambda)

- Added the handle_all_exceptions decorator that is able to catch any type of exception and return a 400 message back.
- Made the Exception friendly message optional in the handle_exceptions decorator.