Add w and h attributes to page number

[s7726]

My OCD kicked in when all the slide numbers were statically sized to flow off the slide.

PptxGenJS/dist/pptxgen.js

Line 1123 in 8c8cea7

+ ' <a:xfrm><a:off x="'+ getSmartParseNumber(slideObject.slideNumberObj.x, 'X') +'" y="'+ getSmartParseNumber(slideObject.slideNumberObj.y, 'Y') +'"/><a:ext cx="800000" cy="300000"/></a:xfrm>'

The following change (sorry not in a spot to do a proper pull request right now) adds w and h to the slide number options.

					+ '    <a:xfrm><a:off x="'+ getSmartParseNumber(slideObject.slideNumberObj.x, 'X') +'" y="'+ getSmartParseNumber(slideObject.slideNumberObj.y, 'Y') +'"/>'
					+ '    <a:ext cx="'+ getSmartParseNumber(slideObject.slideNumberObj.w, 'X') +'" cy="'+ getSmartParseNumber(slideObject.slideNumberObj.h, 'Y') +'"/></a:xfrm>'

[gitbrent]

Hi @s7726,

Thanks for your contribution!