fix: ensure initialization completes on subsequent attempts

[techfg]

IMPORTANT

What is this change for?

• Feature / enhancement - Any change should be discussed in the associated Issue before proceeding. Failure to do so may result in the rejection of the pull request.
• Bug
• Docs
• Tests

Description (required)

The underlying issue is actually a regression from 0aca845 way back in October 2011. In that commit, there was an change in approach to how deferred methods were executed. Prior to the commit, when the situation arose were initialization was called but something else was "in-flight", bind (the equivalent of initialization) was added to the command processing queue. However, in the change, Lines 2165 thru 2172, img.bind was put in its place which would actually call the jquery.bind method (aka. jquery.on) to register an event listener. The changes in this commit are the root cause of why this bug currently exists.

Since the above commit, the code was calling jquery.bind with no parameters which actually does nothing and even with parameters, would not have been an equivalent replacement in functionality to the previous queue_command that was called.

In 48125a6, the img.unbind was fixed to properly queue an unbind command, however the img.bind was not updated/fixed.

In this commit, bind was changed to on since bind was deprecated in jQuery 3.

Finally, in this commit, on was removed entirely since it does not do anything to begin with (see above).

In short, the change made in 0aca845 was incorrect and it should have queued a bind/initialization when map data is already present. This ensures that the unbind called just prior completes fully before mapster is reinitialized.

This PR corrects the issue and ensures mapster is successfully initialized even on multiple initialization calls.

Test plan (required)

• Tests were added to events suite
• Multiple Initialization test page was added to examples

Closing issues

Closes #427