Make the readme more modern, and point github visitors at our real home

README

-Krita
-
-Krita is a paint application for raster images. It's also, according to
-the Dictionary of Phrase and Fable:
-
-The first of four Hindu periods contained in the great Yuga, when the
-genius of Truth and Right, in the form of bull, stood firm on his four
-feet, and man gained nothing by iniquity.
-
-In the Mahabharata, the name 'krita' is used in a context where this
-can be translated with 'perfect' - the perfect age.
-
-Krita is Swedish for chalk and rita means "to draw".
-
-
-You can find more information at: http://www.krita.org

README.md

+Krita
+
+Krita is a free and opensource digital painting application. If you're 
+reading this on Github, be aware that this is just a mirror. Our real
+code repository home is KDE:
+
+    https://phabricator.kde.org/diffusion/KRITA/.
+
+The user manual is here:
+
+    https://userbase.kde.org/Krita/Manual
+
+Development notes and build instructions:
+
+    https://community.kde.org/Krita
+
+Bugs and wishes:
+
+  https://bugs.kde.org/buglist.cgi?bug_status=UNCONFIRMED&bug_status=CONFIRMED&bug_status=ASSIGNED&bug_status=REOPENED&list_id=1315444&product=krita&query_format=advanced
+
+Discussion forum:
+
+    http://forum.kde.org/viewforum.php?f=136
+
+IRC channel:
+
+    irc.freenode.net, #krita
+
+And our website:
+
+    http://www.krita.org