SVGHMI : still trying to optimize. Added xslt code to identitfy minimum set of elements needed by a particular page. Plan is to remove unseen/unused elements from the DOM, and re-appending them later when used, on page switch. Disabled previous optimization.

SVGHMI: attempt to optimize for webkit, because of really slow style recompute in svg:use : "unlink clones" (as in inkscape) but stop deep-copy when meeting a widget, and create a new clone instead.

SVGHMI: optimize browser work by hiding (display:none) pages that are not displayed.

SVGHMI: Better and less verbose SVG namespace handling in XSLT transform

SVGHMI: Added mostly untested switch widget

SVGHMI: HMI:Page can now be a svg:g group or a svg:use clone, and included/linked widget are included in page. HMI:Jump was updated to be clickable through svg:use, to be generalized.

SVGHMI: ensure that coordinate in CSV file generated by inkscape are both matching svg default unit and in default reference frame