denature: delete backup files generated by a vim-like text editor

Signed-off-by: Wolfgang Richter <wolf@cs.cmu.edu>
denature: text files need not be executable

- changed permissions from 755 to 664

Signed-off-by: Wolfgang Richter <wolf@cs.cmu.edu>
Merge pull request #3 from theonewolf/cleanup

Cleanup denature sub-project