Release v0.3.18

What's Changed

• Fix shadowed dir variable in TestMain by @mattn in #152
• Fix env var substitution regex by @mattn in #154
• Validate GOREMAN_RPC_PORT by @mattn in #158
• Skip indented comment lines in Procfile by @mattn in #160
• Fix RPC recover re-panicking on non-error panic values by @mattn in #155
• Fix data race in Status RPC by @mattn in #156
• Fix exported upstart PORT values by @mattn in #153
• Error on unknown export format by @mattn in #161
• Close RPC listener on shutdown by @mattn in #157
• Parse .env with godotenv in export by @mattn in #162
• Fix logger goroutine leak on restart by @mattn in #159

Full Changelog: v0.3.17...v0.3.18