Merge pull request #81 from coreos/fixLog

Fix log
Merge pull request #82 from coreos/master

write multiple entries with a buffered io
Merge pull request #84 from coreos/Initialization

Initialization
Merge pull request #85 from coreos/Initialization

update leader name when server is follower
Merge pull request #86 from coreos/Initialization

change join command to interface, so application can overwrite it
Merge pull request #87 from coreos/master

expose loglevel api to application
Merge pull request #88 from coreos/master

encode entry should reuse memory rather than alloc each time
Perfunctory gofmt -w -s=true.
Simplify Protobuf Encoding by Removing Buffers

This commit removes the explicit Protocol Buffer coding buffer, for
goprotobuf's proto.{Marshal,Unmarshal} automatically allocate an
empty buffer, just like the original code did.
Merge pull request #90 from matttproud/refactor/coding/simplification

Simplify Protobuf Encoding by Removing Extraneous Buffers
fix log_entry.go