1) documentation.

2) default to String type if type is omitted.

3) use Properties.store (or .save) to write the property file.

Submitted by:	Jesse Tilly <JTilly@hoteltools.com>

I've modified Jesse's original patch to make it compile on JDK 1.1.


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@268153 13f79535-47bb-0310-9956-ffa450edef68