Introduce a new property magolia.developement

During developement the files are not in a jar but in the classes directory (this is the main reason why the module bootsraps by default only the config.modules.modulename.* files and not every file found)

Javascript:
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The javascript files are streamed from the resources and therefore cached. If the property is true we read the files directly from the classes directory instead of using getResourceAsStream().

JSP

We should not use JSP in the longer run for the admin templates: use the dynamically registerable page handlers instead. How ever if the developement flag is true and the system supports links it should not copy the content from classes/mgnl-content. Instead it should make links to this directories.