Add lens support for request cookies

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extra : amend_source : 2888f343f63fb0380da4b8778988f7bd576c3df4
Super-basic session support
Add session post support
Refactor cookie overriding
Add session head support
Add session support for other HTTP verbs
Sessions: tie cookie and connection management together

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extra : amend_source : 467ca1d9b59b293a11b79fe57f251b8b700e7673