(Bug 5067) Recognize "-" in potential usernames in markdown

So @dw-suggestions and @dw_suggestions will both work.
(Bug 4726) move /bin/styles to /styles
-- also edit update-db to point to new location
Merge pull request #436 from afuna/markdown-username-hyphen-bug5067

(Bug 5067) Recognize "-" in potential usernames in markdown
Merge pull request #439 from ninetyd/bug4726/move_/bin/styles

(Bug 4726) move /bin/styles to /styles