Use Guzzle components rather than the full-stack
merged branch thewilkybarkid/guzzle-components (PR #111)

This PR was squashed before being merged into the master branch (closes #111).

Discussion
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Use Guzzle components rather than the full-stack

This changes Goutte so that it only requires the Guzzle HTTP component rather than the full-stack, dramatically reducing the size of the PHAR (~3.5MB to under 1).

The history/mock Guzzle plugins are dev-required.

The BC "break" here would be if someone was using other parts of Guzzle, but they should be listing them as their own dependencies anyhow.

Commits
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7b44344 Use Guzzle components rather than the full-stack
updated deps
updated the phar