Add options to constructor; pass object to wait_* handlers

[scottgifford]

• Adds options to the constructor, including:
  • Details: Set to 0 to get a single notification of some change, instead of one notification
    for each change
  • Latency: Set the time to wait for notification. Sets the FSEvents latency, or the sleep time
    for the timer method
  • Method: Choose a method, instead of auto-detecting.
• Adds documentation of these options
• Pass object to the various wait_* handlers, so they can see the object's properties

[scottgifford]

Hello miyagawa,

Any comments on these changes?

Thanks!

----Scott.