Fix four instances — one in The Rise of Wesnoth’s dialog, two in the
ogre race description, and one in the “LAN server” “motd” — of the
straight apostrophe (U+0027 ' APOSTROPHE) being used in player-visible
text, where the typographic apostrophe (U+2019 ’ RIGHT SINGLE QUOTATION
MARK) ought to be used instead.
Fix two minor textual errors in the value of the `motd` attribute in
data/lan_server.cfg:
* “Wesnoth” was not capitalized when it ought to have been capitalized.
* “shutdown” was used as a verb. “shutdown” is a noun; the verb is “shut
down”.
