tell json encoder polling_interval_multiplier is encoded as string type

add masked variable support for gitlab projects and groups

[Merge requests API] Add missing field: merge_error

Add support for merge_requests_author_approval in ApprovalConfigurations

Add AvatarURL and WebURL to MergeRequest resource

There are already available in v11.11.2
https://docs.gitlab.com/ee/api/merge_requests.html#get-single-mr

Make a custom marshaller for merge params

Fixes #626

Project Import/Export API

Update Jira service: change JiraTransitionID from int to string

Added custom writer to Archive

Add Fork Project Options

add "managed" flag for toggling managed clusters during create

The gitlab api has a "managed" field to disable cluster management features when adding a kubernetes cluster. This implements that field. Default is true if you don't supply it.

updatedById is not an array of int but an object like other fields

Added field which shows if the branch is default

Added "default" field, which shows if the branch is default in its project

Escape ProtectedTags tag wildcards

When protecting tags, it's very normal to use characters that are not
safe to use in a url like `/` or `*`. This change should make it safe.