Usages of Logger.entering and Logger.exiting

[jsjason]

The methods Logger.entering() and Logger.exiting() are in some classes, mostly for debugging purposes. REEF also has these methods in various classes, mainly the group communication classes. However, I do feel a bit doubtful about glittering methods with entering() and exiting(). If they're not very useful, we could just take them out instead of using up extra lines. I'd like to know how the others think.

[yunseong]

+1 to take them out. I've observed that the log entries are not easy to parse. Any other thoughts?

[jsjason]

We might as well and create a PR for this one. Though, we should make sure that taking out all instances of LOG.entering/exiting truly doesn't matter for any of us.