Merge pull request #3 from hhy/daniel-failuredetection

Merge changes from failure detection branch
MessageType created. A bit of work on the front-end
finish frontend, except the message sending part
finish frontend, except the message sending part
temp
clean up the FE, and create an interface for FE to call for sending the message
start server and fe demo
Merge branches 'master' and 'hhy'
Merge branch 'master' of https://github.com/hhy/soen.git

Conflicts:
	common/Message.java
	frontEnd/FE.java
add getProcessID
update election and MachineInfo
Merge pull request #4 from hhy/master

Merging from master (haiyang's changes)