TSLint/ESLint in the new platform

[kimjoar]

We need to explore TSLint and/or ESLint in the context of the new platform, e.g. we must fail when trying to import outside any plugins directory.

Things to potentially explore:

• TSLint vs ESLint? I expect TSLint can give us TypeScript specific errors, but maybe ESLint is enough? Should do some testing
• We should consider disallowing any use of process within Kibana. It feels like that should only happen in the CLI, e.g. no process.exit etc within Kibana itself.

[epixa]

I'm going to close this for now. It's a good idea, but we should create specific issues for specific rules/changes rather than having a generic issue without a concrete "end".