Don't include path to depswriter.py, since it may vary, causing noise in source control.

Fixes #149
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=101626615

Author: joeltine

closure/bin/build/depswriter.py

@@ -201,7 +201,8 @@ def main():
   else:
     out = sys.stdout
 
-  out.write('// This file was autogenerated by %s.\n' % sys.argv[0])
+  out.write(('// This file was autogenerated by %s.\n' %
+             os.path.basename(__file__)))
   out.write('// Please do not edit.\n')
 
   out.write(MakeDepsFile(path_to_source))