support for @property on classes (including tests)

[aidinabedi]

We need support for class properties and since #73 has not been updated since May. I decided to take it upon myself to fulfill the requirement regarding tests, as stated in #73 (comment).

So this PR is based on the work done by @HackbrettXXX, with the addition of test cases. See output: https://travis-ci.org/englercj/tsd-jsdoc/builds/575963771#L251

[englercj]

Thanks @aidinabedi for adding tests. Glad you did, because it looks like PropTest3 and PropTest6 are not valid Typescript.

They both contain:

{
    myProp: boolean;
    myProp: boolean;
}

[aidinabedi]

It's not the job of tsd-jsdoc to output valid TypeScript in that test. The output is intentionally meant to be duplicate properties because I wrote "invalid" jsdoc comments, i.e. describing the same property twice. Which I could just as well do using other jsdoc tags (without the PR). I wanted to have a test to make sure the behavior is still the same, and tsd-jsdoc isn't trying to be smart in this "special" case. To quote the readme:

This library provides very little validation beyond what JSDoc provides. Meaning if you have invalid JSDoc comments, this will likely output an invalid TypeScript Definition File.

[aidinabedi]

@englercj I've added additional duplicates to illustrate that the behavior is the same, whether you use @property or regular @type tags.

[englercj]

Fair enough.

[HackbrettXXX]

Thanks for providing the tests @aidinabedi. Couldn't find the time myself.

[aidinabedi]

@HackbrettXXX No problem!