# Functions
New takes a maxLockTime and returns a lock.
NewLimiter returns a Limiter with the supplied limit.
# Variables
ErrStopped is returned by ThreadGroup methods if Stop has already been called.
# Structs
A Limiter restricts access to a resource.
RWMutex provides locking functions, and an ability to detect and remove deadlocks.
A ThreadGroup is a one-time-use object to manage the life cycle of a group of threads.
TryMutex provides a mutex that allows you to attempt to grab a mutex, and then fail if the mutex is either not grabbed immediately or is not grabbed by the specified duration.
TryRWMutex allows you to try to grab a RWMutex, failing if the mutex is unavailable.