New Rule: All paths in functions should resolve or reject a Promise

[HamletDRC]

This is very similar to #26 (#26)

This code is OK because all paths resolve or reject:

function myMethod() : Promise<void> {
    return new Promise<void>((resolve, reject) => {
        if (something) {
            resolve()
        } else {
            reject();
        }
    });
}

This code creates a violation because not all paths resolve/reject:

function myMethod() : Promise<void> {
    return new Promise<void>((resolve, reject) => {
        if (something) {
            resolve()
        }
    });
}

All of the rules for scope, variable shadowing, and type limitations apply from #26

[arogg]

Tried second example, does not work with tslint 5.11.0 . Any yes I am using the --type-check and --project option :) Other rules from tslint-microsoft-contrib seem to work. ts version 3.1.3 and tslint-microsoft-contrib@5.2.1. and i have strict: true in my tsconfig

[JoshuaKGoldberg]

Hey @arogg, sorry to hear that! Would you mind filing a new issue with the following information:

• File contents (is it exactly the second example, no modifications?)
• Link to your project, if it's open source
• tslint.json contents
• How you're running TSLint, such as on the CLI or via the VS Code extension