[master] Fix for https://java.net/jira/browse/GRIZZLY-1555 (WebappContext needs to convert "." to a real path in order for getResourcePaths() to function properly.)
(cherry picked from commit 0cc9237ee601db3357b8177d2a94c9a62f5578bf)
[master] Fix for https://java.net/jira/browse/GRIZZLY-1126 (Response.sendError(...) should return html error page).
(cherry picked from commit 21909ac7593cf8a6cf8650ce1a715135ad97829c)
[master] Fix copyrights.