Add highlighting for inline-code snippets in haddock

utils/haddock/CHANGES.md

...addock-api/resources/html/Linuwial.std-theme/linuwial.css

...ddock/haddock-api/src/Haddock/Backends/Xhtml/DocMarkup.hs

utils/haddock/html-test/ref/Bug253.html

utils/haddock/html-test/ref/Bug458.html

utils/haddock/html-test/ref/Bug546.html

utils/haddock/html-test/ref/Bug865.html

utils/haddock/html-test/ref/BundledPatterns.html

utils/haddock/html-test/ref/BundledPatterns2.html

utils/haddock/html-test/ref/Hash.html

utils/haddock/html-test/ref/Identifiers.html

utils/haddock/html-test/ref/Math.html

utils/haddock/html-test/ref/NamespacedIdentifiers.html

utils/haddock/html-test/ref/PatternSyns.html

utils/haddock/html-test/ref/PruneWithWarning.html

utils/haddock/html-test/ref/Table.html

utils/haddock/html-test/ref/Test.html

utils/haddock/html-test/ref/Threaded.html

utils/haddock/html-test/ref/Threaded_TH.html

utils/haddock/html-test/ref/Unicode2.html