added joint consensus to some extent
jerkily moving towards a working joint consensus
joint consensus seems, I repeat, seems to work. no guarantees
updated some stuff regarding the list of nodes in Replicas, configuration.OldConfig, configuration.NewConfig
log now uses files
removed some commented code; also initialized nextindex to log.Top() whenever server becomes leader
decrementing nextindex if appendentries response failure
extended make clean to include log-<pid> files as well
re-organized file structures
removed extra debug statements and comments
Merge pull request #1 from saurabhkb/joint-consensus-mostly-works

Joint consensus mostly works