improve outerHTML parameter processing for null, undefined and empty string

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@9192 5f5364db-9458-4db8-a492-e30667be6df6
more tests for url resoving in dynamically opened windows

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@9193 5f5364db-9458-4db8-a492-e30667be6df6
setting outerHTML now works also for detached elements

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@9194 5f5364db-9458-4db8-a492-e30667be6df6
File upload content type shouldn't contain charset

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@9195 5f5364db-9458-4db8-a492-e30667be6df6