Enhancement to increase the standard image support data-URL & SVG-images

[speckyspooky]

On the latest usage of different image types especially "png" & "svg" also with the different usage types of URL-data like source path e.g. "http/https" or in kind of data-URL I figured out that that we have there options to optimize the image support.

Additional on it we have an dependency issue based on the usage of apache-xml-graphics because since version 1.8 the JPGE-transcoder is not longer part of the package. Therefore some svg-transformations (svg-to-image) won't be generated.

My targets are:

1. Improve the standrad handling of SVG-images to get a common handling of svg-images.
2. Solve the issue with the jpeg-transcoder to switch to the png-transcoder
3. Implements more options to support URL-source-implementations
4. Synchronize the preview availablitity of the designer in the best way with HTML, PDF, DOCX, XLSX and PPTX

Additiona information to target 1)
In the first step the svg-images will be handled like the current svg-images which use the transformation into an raster image.
I know this isn't the best way but I will follow the current implementation and in a next step the switch to real svg-images can be done.
(WIth real-svg an separately implementation for each emitter is necessary.)

Screens of the current designer preview with SVG-images & different URL-types

Screens of the current execution of HTML, PDF and DOCX

Screens of the current apache-xmlgraphics library

Source, StackOverflow: https://stackoverflow.com/questions/37899651/convert-a-svg-image-to-a-jpeg-image-using-apache-batik

[speckyspooky]

I will provide a PR for the enhancement.

[speckyspooky]

The PR is provided with the according test documentation & test report.