Update README

Mention that scaling is required.

Describe how to scale.

Describe how to install plugins.
Traduzido para pt_BR
Update README.md
Update to ES-1.1.1
plugins dir and editable config

Plugins can now be installed from a zip file inside <repo>/plugins/.
Configs are now stored inside the repo, so they are editable.
User can create individual config files.
Config files can be pre-processed by erb.
Marker file to limit memory used by ES.
.gitignore
Revert README

README.md was translated to pt_BR, so this commit reverts it and
creates a file README_pt.md, thus README.md is now en_US again.