[SPARK-8886][Documentation]python Style update

Fixed comment given by rxin

Author: Tijo Thomas <tijoparacka@gmail.com>

Closes #7281 from tijoparacka/modification_for_python_style and squashes the following commits:

6334e21 [Tijo Thomas] removed space
3de4cd8 [Tijo Thomas] python Style update

docs/sql-programming-guide.md

@@ -1798,7 +1798,7 @@ DataFrame jdbcDF = sqlContext.read().format("jdbc"). options(options).load();
 
 {% highlight python %}
 
-df = sqlContext.read.format('jdbc').options(url = 'jdbc:postgresql:dbserver', dbtable='schema.tablename').load()
+df = sqlContext.read.format('jdbc').options(url='jdbc:postgresql:dbserver', dbtable='schema.tablename').load()
 
 {% endhighlight %}