#580 Change getting of content to skip whitespace text nodes using `ContentSource`  values: `FirstChildTextNode`, `LastChildTextNode` and `ChildTextNodesTrimmedAndSpaceJoined`
#580 Change getting of content to skip whitespace text nodes using `ContentSource`  values: `FirstChildTextNode`, `LastChildTextNode` and `ChildTextNodesTrimmedAndSpaceJoined`

YevgeniyShunevych/Atata,atata-framework/atata,YevgeniyShunevych/Atata,atata-framework/atata