Add React components for each format type

This adds React components for each format type, e.g. `Number`, `Date`,
`Message`, et al. These components have been added in a way that's
backwards compatible with v1.0.0.

The new way to use this package is to reference the new `ReactIntl`
global in the browser, or use `var ReactIntl = require('react-intl');`
in Node.js.

Instead of the Mixin being the default export, the `ReactIntl` module
now contains a named export for each component, the mixin, and the
function to add locale data. Completely they are:

```
// Component Mixin:
ReactIntl.Mixin

// Components: (e.g., <Number style="percent">{0.9}</Number>)
ReactIntl.Date
ReactIntl.Time
ReactIntl.Relative
ReactIntl.Number
ReactIntl.Message

// Function to add locale data:
ReactIntl.__addLocaleData
```

**Note:** This should be safe to release as `v1.1.0` as all back-compat
is maintained.

Closes #23
Upgrade grunt-bundle-jsnext-lib

This also organizes the components under `src/components/`
Fix cwd path in Gruntfile
Update index.js to iterate named exports
Add <HTMLMessage> component

This adds support for an <HTMLMessage> component that will work with
ICU messages that contain HTML in them. It first HTML-escapes all
string props before formatting the message, then it uses
`dangerouslySetInnerHTML` so React won't try to escape the contents.

Closes #26
Clean-up components' render() and displayName
Add support for configured tagName to HTMLMessage
Update example to render using components
Upgrade to grunt-bundle-jsnext-lib@0.4
Merge remote-tracking branch 'upstream/master' into components

Conflicts:
	example/index.html
Update smoke tests for React 0.12 and components
Merge branch 'master' into components

Conflicts:
	Gruntfile.js
	package.json
Merge branch 'master' into components

Conflicts:
	index.js
Rebuild for Components