rename controller skeleton template files to twig extension
merged branch tgabi333/master (PR #206)

This PR was merged into the master branch.

Discussion
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[SensioGeneratorBundle] Rename skeleton template files to twig extension

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | none
| License       | MIT
| Doc PR        | none

In our system, we make a pre-commit syntax validation based on extension of files. But these files are twig templates not phps.

Commits
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68ff899 rename controller skeleton template files to twig extension