[MINOR][DOC] Update deprecation notes on Python/Hadoop.

Author: dongjoon-hyun

docs/index.md

@@ -26,15 +26,13 @@ Spark runs on both Windows and UNIX-like systems (e.g. Linux, Mac OS). It's easy
 locally on one machine --- all you need is to have `java` installed on your system `PATH`,
 or the `JAVA_HOME` environment variable pointing to a Java installation.
 
-Spark runs on Java 8+, Python 2.6+/3.4+ and R 3.1+. For the Scala API, Spark {{site.SPARK_VERSION}}
+Spark runs on Java 8+, Python 2.7+/3.4+ and R 3.1+. For the Scala API, Spark {{site.SPARK_VERSION}}
 uses Scala {{site.SCALA_BINARY_VERSION}}. You will need to use a compatible Scala version
 ({{site.SCALA_BINARY_VERSION}}.x).
 
-Note that support for Java 7 was removed as of Spark 2.2.0.
+Note that support for Java 7, Python 2.6 and old Hadoop versions before 2.6.5 were removed as of Spark 2.2.0.
 
-Note that support for Python 2.6 is deprecated as of Spark 2.0.0, and support for 
-Scala 2.10 and versions of Hadoop before 2.6 are deprecated as of Spark 2.1.0, and may be 
-removed in Spark 2.2.0.
+Note that support for Scala 2.10 is deprecated as of Spark 2.1.0, and may be removed in Spark 2.3.0.
 
 # Running the Examples and Shell