Change position of the Studio tab in update center and the layout of the information inside

• Studio tab should be placed just after "Nuxeo Software Update" tab
• Studio tab should be renamed "Studio" instead of "Studio configuration package"
• The tab should have an introductary zone with two links then two areas separated with clear titles:

First paragraph:To know more about Studio, go to the <href="https://doc.nuxeo.com/display/Studio/Nuxeo+Studio+Documentation+Center" Studio documentation center </href>.
Second pragraph: Go to your Studio project : <href="directl link to project in studio">project title</href>

Then the two main parties of the tab

"Development/configuration mode"
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Use the "Update" button when you want to update the Studio plugin with what you are currently configuring in Studio. The update button will change on the Nuxeo instance the version of your Studio plugin with a new one that includes the latest configuration done in Studio. Most of the features configured in Studio don't need to restart the server, so that you can immediately test the consequence of your configuration.

***Update button****

"Production mode"
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(note: "production" may not be the good english translation...)
If you have tagged a version of your plugin (<href ="https://doc.nuxeo.com/display/Studio/Version+Control#VersionControl-creatingtag") read how to tag your Studio plugin</href>)you can install a tagged version, which is the recommended way for a production instance. Click on refresh to update the list if you have just tag something.

*********List of the the tags*************