Upgrade to rustc 1.0.0-nightly (4db0b3246 2015-02-25) (built 2015-02-26)
Upgrade to rustc 1.0.0-nightly (4db0b3246 2015-02-25) (built 2015-02-26)

servo/string-cache,dzbarsky/string-cache,huonw/string-cache,nox/string-cache,tempbottle/string-cache,frewsxcv/string-cache