Implement issue list

I had to iterate through user's accessible projects as it seems that the API is buggy, at least with an LDAP auth

I will investigate later
Remove AuthListener as it seems useless
Implement more issues related features
Implement updateIssue (issue:assign)
Implement getMilestones (issue:list:milestones)
Implement getPullRequests (pull-request:list)
Results filtering on issue:list & pull-request:list commands
Fix a cast on issues
Implement MR commands
Throw exception in unsupported methods
Clean adapter
Process source & target branch property
Fix issue:create
Handles issues' comments
Be compliant with new interface
Add configurator
Merge pull request #1 from jubianchi/migrate-gitlab-api-lib-new-interface

This PR was merged into jubianchi:migrate-gitlab-api-lib branch.

Discussion
----------

Conform to new adapter API

                   
|Q            |A  |
|---          |---|
|Bug Fix?     |n  |
|New Feature? |y  |
|BC Breaks?   |n  |
|Deprecations?|n  |
|Tests Pass?  |y  |
|Fixed Tickets|   |
|License      |MIT|
|Doc PR       |   |
                   


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Commits
-------

5d11fc8c572042e26255038cab0443867e7dce2a Be compliant with new interface jubianchi
1033553ba5ab1aaffda146fff1fe5b9dbbf86bb7 Add configurator jubianchi
Add vagrant VM
Implement supportsRepository
Clean