Changes endpoint for /node/
Adds tests sensor GET and POST
Fixes tests to comply with new Helper format
Adds more exceptions
Renames file && converts helper methods to staticmethods
Moves ApiResponse class to separate file
Renames set_environment to set_database_environment
Cleans up && adds NodeList resource && adds sensor POST handler and routes
Adds POST and GET tests for Site resource
Adds new exception
Adds more tests for reading resource
Reading resource now passes tests, but NO time filtering is yet implemented
bugfix