Prepare Release 1.7

Merge pull request #585 from fzaninotto/prepare_1_5

Prepare 1.5 release

Releasing v1.4.0

Fix composer version

Update composer branch alias

Add CHANGELOG

Update Lorem provider to remove WTF effect.

`Lorem::words()`, and `Lorem::sentences()` can now return an exact number of words or paragraphs thanks to a second parameter.
`Lorem::text()` now works for small number of characters by being smarter.

Closes #47.