First version of the code

I commit to initialize the repo ... with a first version of the full
plugin code and a single demo page (architecture has to be reviewed)
Directory architecture

The plugin sources are in the "src/" directory
Clean up the MacOSX stuf

… I set it in the gitignore
I refound the lifecycle of tooltips

Tooltips can now be fully replaced by the jQuery UI tooltip feature,
and a part of the code had been re-written to clarify some stuff ...
New demo design

The design of the demonstration pages is reviewed and some
micro-corrections on the code. I think it's ready for the 1.0 version
(after a little check)
Version 1.0.0
Renaming "PieroWbmstr" in lowercase