flexmark-java extension for image's size 0.64.6 API

flexmark-java extension enables to set width and height for images by stating them as ![text](/src =WxH) which is used in Azure DevOps markdown.

Converts ![text](/src =WxH) into image with width = W and height = H. Also added support for image`s relative paths from Azure DevOps repository.

Packages 
Package Description
com.vladsch.flexmark.ext.resizable.image