Fix "setup.py install" referencing the correct front end script.

This commit updates setup.py to account for changes introduced by cce6e2c5.
It fixes the following error:

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[...]
running install_scripts
running build_scripts
creating build/scripts-2.7
error: file '/path/to/ctk-cli-indexer/cli_to_json.py' does not exist
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Merge pull request #6 from jcfr/fix-setup-install

Fix "setup.py install" referencing the correct front end script.