Use new-style HLint comments

[georgefst]

My primary motivation for this is cross-compiling SBV. Before this change, this wasn't possible due to the warning Ignoring ANN annotation, because this is a stage-1 compiler without -fexternal-interpreter or doesn't support GHCi, combined with -Werror. With the change, it's only blocked by #659.

Out of interest:

• Why -Werror? It's unusual to use it everywhere, and Hackage even bans uploading packages which enable it globally, which SBV appears to work around by enabling it in every individual file instead.
• What is this project's HLint policy? The Data folder is HLint-clean, but Documentation and SBVTestSuite contain some ignore pragmas but also trigger other hints which aren't ignored. Also, based on the numbers of HLint warnings which remain when all ignore pragmas are removed, many of them are redundant. Maybe putting the pragmas near use sites, as is conventional, would help see when these can be removed (although ideally HLint itself would be able to check this)

[LeventErkok]

Do these have an extra stray $ at the end of each hint? Looks odd to me. And the hlint check fails on them. See below.

[georgefst]

Ah, yes, sorry, I am genuinely unsure how I managed to mess that up. Fixed now.

[LeventErkok]

Thanks for the PR. Regarding your specific questions:

1. -Werror is my personal preference. SBV never claimed to work with anything but the latest GHC, and I keep track of the changes in GHC to make sure it compiles cleanly with it. Nothing deeper than that.
2. HLint policy is to keep it lint-free when I run the following target in the Makefile: https://github.com/LeventErkok/sbv/blob/3bdc3fdb804d74f7f654c841bae1c42c6c9e789d/Makefile#L73-L74 Looks like I'm not checking the "Documentation" directory; that's an oversight which I'll fix. It's of course entirely possible that some pragmas are outdated, or they can be reduced; but in a project like SBV that's been around for more than a decade, this sort of cruft accumulates. Happy to accept PRs that improve the hlint pragmas anytime.