Restore source code use via "download/get/*.js"

[SergioCrisostomo]

fixes #199

2 commits:

• 48b457f to add source files for old versions < 1.5
• fc97e1b to add the download functionality

This PR restores a functionality that was available in the old website. To be able to download Core's source files via url http://mootools.net/download/get/<version>.js. This was used both by users and jsFiddle.

So basically:

• old versions will be served as before. (example: mootools-1.2.6-core-nc.js, or mootools-core-1.4.5-full-compat-yc.js).
• Version starting at 1.5.0 will be compiled live and accept both Google CDNs naming*, and our own that comes with a new download from the website.

[SergioCrisostomo]

Refactored this PR and updated the description above.
Review input welcome.

[arian]

I'm not really sure we really miss this functionality.

[SergioCrisostomo]

@arian we were discussing yesterday in #irc with zalun that jsFiddle is broken in older versions because of this (http://jsfiddle.net/h424aykm/), and apparently some people like @olvlvl were using it also.

[olvlvl]

It's nice to have this back. Although we can use the CDN, it only serves one flavor : .min.js.

[SergioCrisostomo]

We talked more about this in the #IRC-dev channel and decided to not add this feature, so mootools.net will not be used as a CDN.

Google's CDN has actually different versions, just they don't point it out. (maybe we could ask them to change that).

So for example for 1.5.1 we have:

• compat: https://ajax.googleapis.com/ajax/libs/mootools/1.5.1/mootools.js
• compat compressed: https://ajax.googleapis.com/ajax/libs/mootools/1.5.1/mootools-yui-compressed.js
• no-compat: https://ajax.googleapis.com/ajax/libs/mootools/1.5.1/mootools-nocompat.js
• no-compat compressed: https://ajax.googleapis.com/ajax/libs/mootools/1.5.1/mootools-nocompat-yui-compressed.js