Added support for managing files by pillar

Change-Id: Ibd0a024bcd69089d9835a18f2bb803c952e13967
diff --git a/README.rst b/README.rst
index 8628f80..027f493 100644
--- a/README.rst
+++ b/README.rst
@@ -341,6 +341,41 @@
             mode: 700
             makedirs: true
 
+Ensure presence of file by specifying it's source:
+
+.. code-block:: yaml
+
+    linux:
+      system:
+        file:
+          /tmp/test.txt:
+            source: http://example.com/test.txt
+            user: root
+            group: root
+            file_mode: 700
+            dir_mode: 700
+            encoding: utf-8
+            hash: <<md5 hash>>
+            makedirs: true
+
+Ensure presence of file by specifying it's contents:
+
+.. code-block:: yaml
+
+    linux:
+      system:
+        file:
+          /tmp/test.txt:
+            contents: |
+              line1
+              line2
+            user: root
+            group: root
+            file_mode: 700
+            dir_mode: 700
+            encoding: utf-8
+            hash: <<md5 hash>>
+            makedirs: true
 Kernel
 ~~~~~~