Made hack-wish work properly.
Add newline to autotrade usage

Fixes #304
Make plugins use ".plug.dylib" extension on OS X
Update NEWS
Merge commit 'baeb894'
Update NEWS.
Merge remote-tracking branch 'lethosor/autotrade-usage-newline'
Merge remote-tracking branch 'lethosor/osx-plug-dylib'

Conflicts:
	NEWS
Merge remote-tracking branch 'dfhack/develop'
Update xml.