Removed the naive minimalExpansionSequents algorithm since it is unusably slow. 


git-svn-id: http://gapt.googlecode.com/svn/trunk/source@2265 85d21ef8-add0-11de-ae77-5bfb9c5a3f34
Improved ProofTool performance when reordering expansion trees. Moreover, there is now an option "Reset" in the context menu for the title labels that will return the sequent on that side to the original order and close everything.


git-svn-id: http://gapt.googlecode.com/svn/trunk/source@2266 85d21ef8-add0-11de-ae77-5bfb9c5a3f34