[PATCH]Small extension to -projecthelp option and doc updates

[Marcel Schutte <ma...@schutte.com>]

Hi,

I've updated the commandline option -projecthelp to output two sorted list
of targets, those with and those without a description. This way you get a
hint as to which targets are meant to be called from the outside and which
are more like internal targets, without losing the complete picture.
And ofcourse I also updated the docs :), ahum should have done that the
first time around. The patches for build.xml and buildant.xml are a first
try to use descriptions on ant itself. Could someone check to see if there
are more targets that are meant to be called directly?

A second smaller documentation change was triggered by Paul Arzul's question
on ant-user: the possibility to specify more than one target on the
commandline was not documented.

Regards,
Marcel