merged olivier's push to scala 2.11. thanks a lot! 

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@2091 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
small bugfix in ceres(schema), started removing Pair deprecation warnings

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@2093 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
removing intellij project file

git-svn-id: http://gapt.googlecode.com/svn/trunk/source@2094 85d21ef8-add0-11de-ae77-5bfb9c5a3f34