AVars emulate mutable variables, by providing a queue based interface to interacting with the variable. Each variable runs a handler function, which reads requests from a queue and processes them one by one. They can be used in concurrent systems safely, and should handle exceptions thrown by modifying functions gracefully. There is also an unsafe interface through Data.AVar.Unsafe, which will throw any errors encountered while modifying the variable. New in this version: * Fixed a (MASSIVE) mistake where i had forgotten to export the newAVar function. * Gave in and exported Data.AVar.Internal