dev-haskell/sha: bump up to 1.6.2.1

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
dev-haskell/pointfree: Fix trailing whitespace
dev-haskell/cabal: Remove useless blank line
dev-haskell/xml-catalog: Fix trailing whitespace
dev-haskell/happstack: Remove useless blank line
dev-haskell/heist: Remove useless blank line
Improve HOWTO-Contribute
Improve README