Add a new function

void TBranch::DeleteBaskets(Option_t* option)
   // Loop on all branch baskets. If the file where branch buffers reside is
   // writable, free the disk space associated to the baskets of the branch,
   // then call Reset(). If the option contains "all", delete also the baskets
   // for the subbranches.
   // The branch is reset.
   // NOTE that this function must be used with extreme care. Deleting branch baskets
   // fragments the file and may introduce inefficiencies when adding new entries
   // in the Tree or later on when reading the Tree.


git-svn-id: http://root.cern.ch/svn/root/trunk@23378 27541ba8-7e3a-0410-8455-c3a389f83636