Extract services from comments controller

[KentShikama]

For the comments API routes

[jhass]

I tend to prefer Ruby core's naming convention of not having a bang! method if there's no nonbang variant.

[jhass]

For Post you did one that service that does both, creation and destruction. Having separate ones for Comment now feels a bit inconsistent to me.

[KentShikama]

For posts I put the show and destroy together in one service and the create in another service. I suppose I should just separate the show and destroy service for the posts?

[jhass]

I think I wouldn't mind a service per model. Currently we have about what, a dozen resources? With two to four of the CRUD actions that's 30-40 services.

[KentShikama]

Yeah sounds good; I'll merge them together then 👍

[jhass]

Merged as d7c9243

Thanks!