rename changes file and add a known-issues file

(cherry picked from commit 84bca22f)

dist/changes-2.1.0 → dist/changes-2.0.1

-The QtCreator 2.1 release contains bug fixes and new features.
+The QtCreator 2.0.1 release contains mainly bug fixes on top of 2.0
 
 Below is a list of relevant changes. You can find a complete list of changes
 within the logs of Qt Creator's sources. Simply check it out from the public git
 repository e.g.,
 
 git clone git://gitorious.org/qt-creator/qt-creator.git
-git log --cherry-pick --pretty=oneline v2.0.0...v2.1.0
+git log --cherry-pick --pretty=oneline v2.0.0...v2.0.1
 
 General
    * Fix the suggested path in the new dialog in case of sub projects