Add a hint to avoid capitalisms

[bgohla]

I add a module Hints.NoCapitalisms that provides a hint to avoid capitalisms in identifiers, with some exceptions. E.g.

module SSL.Foo                                                                                  
class FOO a where
class Foo a where getFOO
data Foo = Bar | BAAZ
getSMS

are discouraged.

The hint has severity Ignored, so it is off by default.

• Things that might need attention

• potentially factor out some code.
• break into several commits.

[bgohla]

If this PR goes ahead, I would propose factoring out the code below.

[arybczak]

What is the reason for this exception? ID? Personally I'd prefer uniformity here.

[bgohla]

That would be one case.

I'm all for uniformity, by I'm afraid not allowing this exception could make this rule very annoying. Let me do some statistics on our internal code base…

[tbidne]

Shouldn't b also be part of the recursive call?

-a:b:c:as -> [a,b,c] : trigrams (c:as)
+a:b:c:as -> [a,b,c] : trigrams (b:c:as)

Otherwise you're missing triples that exist across the boundary e.g.

hasCapitalism "getFOO" === False -- your example, probably not what you want?
hasCapitalism "geFOO" === True   -- should be the same, in any case, right?