add es6 module support

[nicolashenry]

What I have done:

• I converted commonjs modules to ecmascript modules
• I moved sources to src folder (so src/ folder would be dedicated to ecmascript modules and lib/ to commonjs modules)
• I added a new build step to convert ecmascript modules to commonjs modules using babel (src/ to lib/)
• I added lib/ folder to .gitignore and .eslintignore
• I added "module" property and "src/" to files property in package.json.
• I updated pegjs to 0.11.0-master.53b9662 because the "--format=es" pegjs option have not been released yet so this PR will maybe have to wait pegjs 0.11.0 to be released

Fixes #22

[bripkens]

Thank you for this PR. I'll take a look at it over the next weekend. I cannot get to it earlier, sorry.

[bripkens]

So I finally was able to look at this PR. I really like what you did! Once PegJS has been released, we can merge this. Thank you for doing this ❤!

Once merged, we should also address the vulnerabilities the current dependencies have and turn all of this into a new release.

[kf6kjg]

It looks like PEG.js has stalled, the maintainer hasn't had any GitHub activity since January. :(

[bripkens]

Closing due to inactivity.

[kf6kjg]

..? As opposed to just merging this PR? The delay was on your part AFAICT.

[bripkens]

The delay is on the pegjs side as you also summarized in two weeks ago. Truth be told I just went through some of my projects and closed PRs that are open for a long time, but don't make any progress (without a closer inspection of content). So thank you for questioning my action @kf6kjg!

I do very much want to land @nicolashenry's changes, but not based on pre-release version. We can always re-open this PR once pegjs does get a 0.11 release.

[kf6kjg]

Which release might take a new maintainer and possibly a fork: looks like Peg.js's maintainer disappeared several months ago. Reminds me of H2G2: starship waiting on lemon-soaked paper napkins... :P

[saeub]

How about reviving this PR now that peggy is the established successor of PEG.js?

@bripkens are you still maintaining this project?

[bripkens]

@saeub: I don't have an active need for this project atm, but I am willing to review a PR that comes with sufficient test coverage.