README: Remove redundant section
There are two sections about hackage.head. Only the second one mentions the need for cabal update, which just threw me off ( see ghc#20872 (comment 399761)). So let’s remove the first one to avoid confusion.
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There are two sections about hackage.head. Only the second one mentions the need for cabal update, which just threw me off ( see ghc#20872 (comment 399761)). So let’s remove the first one to avoid confusion.