aranged part2 new
Merge branch 'part2' into part3

Conflicts:
	src/com/anderscore/simpleandroidchat/AbstractActivity.java
	src/com/anderscore/simpleandroidchat/ChatActivity.java
	src/com/anderscore/simpleandroidchat/ContactListActivity.java
	src/com/anderscore/simpleandroidchat/ContactListAdapter.java
Added linked list import
added iterator import
Added Abstract Method