* update string extensions IsFullPath to support more filepaths with new built-in Path.IsPathFullyQualified
* resolve TODO to switch to Path.IsPathFullyQualified supported from .NET Standard 2.1
* Use content root instead of web root for uploaded images
* Un-break a breaking change
* handle special parsing of AngularJS json response
* change htmlId selector to support html id's with numbers
* remove bad test case
* test IsFullPath without tricky UNC paths that are not useful
Co-authored-by: Bjarke Berg <mail@bergmania.dk>