Fixed big in get messages and added get recent messages method

This fix was done to address a bug in get chat log and implement get recent chat.

Modified:
.gitignore - modified to ignore .settings as it caused problems with Brandon's IDE
ChatManager.java - get chat log method used the wrong url and is now fixed. Added method that allows the retrieval of recent messages after a given timestamp. Updated URLs.
PullMessageSet.java - Changed constructor to create a copy of the new incoming list. Added constructor that allowed convenient creation of a set that denoted failure.
README.md - removed commit testing messages.

AuthoredBy: colinkho