Yury Yantsevich

Validation warnings

4

Print configuration file validation warnings if: - no files to watch supplied - port is not defined, when host is Exit with error code if no files to watch specified...

Retries [sometimes with delays] feature note. See how it [looks like](https://github.com/featalion/iron_go3/tree/hidden-feature-documentation#important-notes).

Fixes #4. But example Heroku app is not updated.