Remove prev, iojs alias, add quiet mode and more.

[ghost]

Some changes to the script, readme file and package.json file.

• Pulled prev from the script and documentation as discussed in issue remove "prev" command in 1.3 #184.
• Pulled the iojs alias from the script and documentation because it never worked as described in issue iojs alias does nothing #255.
• Added a quiet mode option (-q or --quiet) for curl to not display the progress bar as requested in issue Optional Progress Bar #205.
  • Fixed a "bug" in the install function where curl was hard coded to get the tarball instead of what is set in the GET variable.
  • I also moved the call to tarball_url in the install function below the test for an already installed version. It is a waste to build the url every time and not use it.
• I pulled documentation for n io stable and n io --stable but they still work. They actually work correctly now for io by always calling latest. This was brought up in issue n io stable will install io-v1.2.0 instead of v1.3.0 #230 and I sat on it for a bit. I decided that this would be best for now because it provides backward compatibility.

I also added some minor items from other PRs:
#241 - Added Gitter badge
#239 - Calling n bin would not advance the shell prompt to a new line. I just switched printf to echo.

One final item I pulled is the node keyword which called set_default. It looks like noise because the default state for n would be to install node. I also need the keyword for a feature request in issue #185. To preserve script state I had to add separate functions to install latest and stable so it remembers which mirror to use.

And as @tjwebb said in issue #184 the version was changed to 1.4.0 in the script and package.json files. Or should it be 2.0.0? And if we go to version 2.0.0, maybe I should just make calls to n io (--)stable abort?

[maxrimue]

👍 Looks good!
I think we should go to 2.0.0 since these changes are "incompatible API changes" and therefore are major changes.

[ghost]

Just updated the PR. Put version to 2.0.0 and using n io stable or n io --stable will now abort and report an error because it is not a supported command anymore.

[knownasilya]

Can we pull out --quiet into a separate PR so it can get in quicker (before major bump)?

[ghost]

@tjwebb I merged upstream to clear any conflicts. What is your take on this PR?

[tjwebb]

I wish it were only one feature. It'll take a little awhile to review

[troy0820]

Are we jumping from 1.3.0 to 2.0.0?

[maxrimue]

@troy0820 If we really modify n that much, we should
@tjwebb Is there any progress on the review btw?

[knownasilya]

I say split it out into several PRs, ones that require a major bump and ones that don't.

[tjwebb]

@tedgaydos yea as I mentioned, a PR should contain one thing. No progress on the review, haven't had time. It'll be easier to review if it were multiple PRs, and I agree with @knownasilya

[qw3rtman]

This is a major API change. If we merge these changes, we should update to 2.0.0. 👍

[troy0820]

I agree with @knownasilya and @tjwebb. Multiple pull requests that can eventually push this to 2.0.0.

[ghost]

I will break it up tonight.

[ghost]

Everything is in separate PRs now. See #267, #268, #269, #270, #271

[knownasilya]

@tedgaydos very nice!

[ghost]

@tjwebb It is separated into new PRs. I am closing this one.