another docu link added

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@8438 5f5364db-9458-4db8-a492-e30667be6df6
postMessage is available in real IE 8

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@8439 5f5364db-9458-4db8-a492-e30667be6df6
window.postMessage is synchronous in IE only

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@8440 5f5364db-9458-4db8-a492-e30667be6df6
force build

git-svn-id: svn://svn.code.sf.net/p/htmlunit/code/trunk@8441 5f5364db-9458-4db8-a492-e30667be6df6