Read the key, element pairs from a java properties file
Follows the java properties file format 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