add composer component package

adds support for [component](https://github.com/componentjs/component) and [component installer for composer](http://robloach.github.io/component-installer/)

tested with composer custom repo:
```
        {
            "type": "vcs",
            "url": "https://github.com/glensc/blockui"
        }   
...
    "require": {
        "components/jquery-blockui": "*@dev",

```

after PR merge, probably should:
1. create new git tag in blockui and push it to githu
2. register package on packagist.org