[DOCS] Reorganizes Overview and Installation chapters.

Author: szabosteve

docs/index.asciidoc

@@ -5,10 +5,10 @@ include::{asciidoc-dir}/../../shared/attributes.asciidoc[]
 
 include::overview.asciidoc[]
 
-include::quickstart.asciidoc[]
-
 include::installation.asciidoc[]
 
+include::quickstart.asciidoc[]
+
 include::configuration.asciidoc[]
 
 include::per-request-configuration.asciidoc[]

docs/overview.asciidoc

@@ -5,7 +5,7 @@ This is the official PHP client for {es}. It is designed to be a low-level
 client that does not stray from the REST API.
 
 All methods closely match the REST API, and furthermore, match the method 
-structure of other language clients (Ruby, Python, etc). We hope that this 
+structure of other language clients (Ruby, Python, and so on). We hope that this 
 consistency makes it easy to get started with a client and to seamlessly switch 
 from one language to the next with minimal effort.