Update the `devtools:snapshot` command to use structured commit information when generating changelog.

[shulard]

With the RFC hoaproject/Central#61 we introduce structured commits with the pattern : type(scope) title.

This PR update the changelog step to use this new information when generating the CHANGELOG.md file.

At the moment, all the commits are kept in the resulting file. The non structured ones are stored inside a specific "Commits" sections.

Here an example with the latest hoaproject/Websocket tag :

3.18.01.23

Quality

Composer

• Use dev-master dependencies. (Ivan Enderlin, 2018-01-23T10:42:02+01:00)
• add PHP version requirement (Alexis von Glasow, 2017-08-04T13:48:47+02:00)

PHP

• Update to PHP 7. (Ivan Enderlin, 2017-11-10T10:30:28+01:00)
• Update to PHP 7. (Ivan Enderlin, 2017-11-10T10:13:42+01:00)
• Update to PHP 7. (Ivan Enderlin, 2017-11-08T15:55:02+01:00)
• Fix composer. (Ivan Enderlin, 2017-11-08T15:35:39+01:00)
• Update to PHP 7. (Ivan Enderlin, 2017-11-08T15:33:56+01:00)

CI

• Drop HHVM support. (Stéphane HULARD, 2017-07-07T11:51:42+02:00)

Commits

• Connection: Add close-before event. (Metalaka, 2017-03-30T21:37:26+02:00)
• Fire close event before closing and on error (jmdevince, 2016-04-28T15:15:33-05:00)
• Merge branch 'incoming' into issue_58 (Ivan Enderlin, 2017-03-24T15:18:21+01:00)
• Connection: If a normal close fails, no error. (Ivan Enderlin, 2016-08-04T08:32:03+02:00)
• Connection: Ensure disconnection on closing. (Ivan Enderlin, 2016-08-04T08:29:50+02:00)

[shulard]

Hello,

I've updated the hoaproject/Literature#32 PR with all the defined commit types. I think we are almost good now 😄.

I've just one question about the "First snapshot" changelog. It's generated when the tag list is empty. Actually, the typed commit logic is not applied in that case, is that still on ?