t / t1509 / excludeson commit gc docs: clarify that "gc" doesn't throw away referenced objects (daecbf2)
   1*.o
   2*~
   3*.bak
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   5*.h
   6.git
   7contrib
   8Documentation
   9git-gui
  10gitk-git
  11gitweb
  12t/t4013
  13t/t5100
  14t/t5515