Add 'Haddock' phase

[chshersh]

When building dependencies, you can ask cabal to also build their documentation. This is represented by the Haddock step in the output like this:

Building     base-orphans-0.8.6 (lib)
Haddock      base-orphans-0.8.6 (lib)
Installing   base-orphans-0.8.6 (lib)
Completed    base-orphans-0.8.6 (lib)

Currently, this phase is not supported by dr-cabal but it should be pretty straightforward to add it. Implementation plan:

1. Add new Haddock status here:

dr-cabal/src/DrCabal/Model.hs

Lines 24 to 31 in 89cdcd6

	data Status
	= Downloading
	| Downloaded
	| Starting
	| Building
	| Installing
	| Completed
	deriving stock (Show, Read, Eq, Ord, Enum, Bounded)

2. Add the new phase here:

dr-cabal/src/DrCabal/Profile.hs

Lines 73 to 78 in 89cdcd6

	data Phase = Phase
	{ phaseDownloading :: Word64
	, phaseStarting :: Word64
	, phaseBuilding :: Word64
	, phaseInstalling :: Word64
	}

3. Update phases calculation:

dr-cabal/src/DrCabal/Profile.hs

Line 86 in 89cdcd6

entriesToPhase :: Word64 -> [(Status, Word64)] -> Phase

4. Update legend:

dr-cabal/src/DrCabal/Profile.hs

Lines 143 to 151 in 89cdcd6

	legend :: [Text]
	legend =
	[ b "Legend"
	, " " <> fmt [cyan] block <> " Downloading"
	, " " <> fmt [blue] block <> " Starting"
	, " " <> fmt [red] block <> " Building"
	, " " <> fmt [yellow] block <> " Installing"
	, ""
	]

5. Update profile output:

dr-cabal/src/DrCabal/Profile.hs

Lines 172 to 179 in 89cdcd6

	formatRow :: Text -> Phase -> Text
	formatRow libName phase@Phase{..} = mconcat
	[ fmtPrefix libName phase
	, formatSinglePhase cyan phaseDownloading
	, formatSinglePhase blue phaseStarting
	, formatSinglePhase red phaseBuilding
	, formatSinglePhase yellow phaseInstalling
	]

[diasbruno]

@chshersh I'd like to contribute. Already start working on this one?