Added license in files of sub-folders of EzPC; modified codegen of ezpc to output a autogenerated comment for each compiled file; synced up the test-suite/precompiled_output folder with actual compiled output changes.

1. Bug fix in SeeDot/IRBuilderCSF.py -- for visitFloat() -- had a bug earlier.
2. TFNodesAST -- compilation of mul TensorFlow node
3. Added some more functions in library files of TFEzPCLibrary.