Installer now generates a good project name for composer.json
feature #83 Installer now generates a good project name for composer.json (javiereguiluz)

This PR was squashed before being merged into the 1.0-dev branch (closes #83).

Discussion
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Installer now generates a good project name for composer.json

This fixes #78 and it's completely based on the [code used by Composer](https://github.com/composer/composer/blob/4a3bc58adfd501fa6e82c82fdd9e8d4036898fa1/src/Composer/Command/InitCommand.php#L172-186) and reported by @stof.

In addition to the generation of the project name, this PR reorders and adds missing docs for some methods.

Commits
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d862e51 Installer now generates a good project name for composer.json