Wrong link in crate root docs

[Wanja Hentze]

This line:

arc-swap/src/lib.rs

Line 15 in 1615477

 //! * [`IndependentArcSwap`][ArcSwapOption], which uses slightly different trade-of decisions ‒ see 

refers to IndependentArcSwap but links to ArcSwapOption.

[Michal 'vorner' Vaner]

Thank you. I've fixed in master, but I think it is small enough not to release a new version just because of this. It'll ride with the next release.

[Wanja Hentze]

👍