v0.6.0 Release

What's Changed

• feat: support nested object when generating from terraform schema by @jakezhu9 in #152
• chore: release kcllang/kcl-go docker image by @amyXia1994 in #153
• chore: bump kcl and kpm to latest by @Peefy in #154
• enhance: support schema example in doc gen by @amyXia1994 in #155
• fix: show error message and exit after doc cmd validation error by @amyXia1994 in #158
• minor: add GetSchemaTypeMapping rest api by @amyXia1994 in #159
• feat: add export openapi API by @amyXia1994 in #160
• chore: bump kcl version to v0.6.0 by @Peefy in #162

Full Changelog: v0.5.0...v0.6.0