branch 'dub-integration' was merged in 'master'.

- 'master' is still stable
- a DUB json project can be opened and compiled.
- no error will happen because of a dub project, when a feature is not implemented for a DUB project (and there is a lot of them) what will happen is "nothing".
- in case of bug in version 1, this will not be included. Fixes are put in the '1_fixes' branch.
- a PR for the version 1 should be submitted to the '1_fixes' branch.