Add proxy mode.
Proxy promotion.
Add automatic node promotion / demotion.
Add auto-demotion after peer inactivity.
fix(Documentation/*): fix various typos
Merge pull request #604 from ccding/master

fix trivial issues as I see them
Check for peer before demotion.
Fix JoinCommand comment.
Minor fixes.
feat(scripts/test-cluster): create three proxy nodes

This uses some sleep hackery to make sure that window 1 has followers
and window 2 has proxy machines. Seems to work!
docs(errorcode.md): add the EcodeRootROnly error
Add PHP library.

We implement the api client useing php.
Merge pull request #612 from congpeijun/master

Add PHP library.
Merge pull request #607 from Asmod4n/patch-1

Added Error 107 to Documentation
Merge pull request #4 from philips/benbjohnson-proxy

feat(scripts/test-cluster): create three proxy nodes
Fix PUT /config response and log errors.
Merge branch 'proxy' of https://github.com/benbjohnson/etcd into proxy
docs(CONTRIBUTING): add code style section
Merge pull request #613 from unihorn/29

docs(CONTRIBUTING): add code style section
Add /machines and /machines/:name endpoints.