Recent versions fail to build on GHC 7.6.3

[adamgundry]

See https://matrix.hackage.haskell.org/package/vector-algorithms#GHC-7.6/vector-algorithms-0.7.0.3. It seems that 0.7.0.2 and later use Data.Proxy, which was not exported in GHC 7.6.3. I guess adding a dependency on tagged is the simplest fix, as it will (re)export Data.Proxy as needed.

[erikd]

Fixed in 0.7.0.4.

[adamgundry]

Thanks for the quick fix! My CI script is happy again. 😄