Update README.md

Author: hackorama

README.md

@@ -1,2 +1,18 @@
 java-props-in-python
 ====================
+
+Read the key, element pairs from a java properties file
+
+Follows the [java properties file format](http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html#load(java.io.Reader)) and tested against the Java 6 version of java.util.Properties
+
+Args:
+  propfile: a valid file object (as returned by open(filename))
+Returns:
+  The property key and elements as a dict
+Raises:
+  IOError: if file operation fails with I/O related reason
+    Corresponds to java IOException in Properties.load()
+  UnicodeDecodeError: if the property file has malformed \uxxxx encoding,
+    Corresponds to java IllegalArgumentException in Properties.load()
+  AttributeError: if invalid object was provided for file object
+    Corresponds to java NullPointerException