Auto merge of servo#206 - mbrubeck:debug_unreachable, r=KiChjang

Switch to fork of debug_unreachable

Because the original debug_unreachable is abandoned and doesn't work correctly in modern Rust.

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Auto merge of servo#203 - hcpl:update-deps, r=SimonSapin

Update dependencies

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Auto merge of servo#203 - hcpl:update-deps, r=SimonSapin

Update dependencies

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Serde update is a breaking change

Auto merge of servo#189 - servo:stack-case, r=nox

Avoid some allocations in to_ascii_{upper,lower}case

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Auto merge of servo#182 - nox:serde, r=jdm

Update serde to 0.9

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Cargo insists on no shared files between crates.