dynamic database name

[man-of-fox]

Feature: database name can be dynamicaly provided as string oder context variable on "mongo in" and "mongo out"

• [ ] Bugfix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)

Proposed changes

missing feature to provide database name optionaly as context variable for example to use req.headers.host (without port) as database name. With that you can use same application with diferent data backends definded by query parameter, post data or in my case with domain name.

Checklist

• [ ] I have read the contribution guidelines
• [ ] For non-bugfix PRs, I have discussed this change on the forum/slack team.
• [ ] I have run grunt to verify the unit tests pass
• [ ] I have added suitable unit tests to cover the new/changed functionality

[hardillb]

Do you have a link to where this change was discussed (Slack or Forum)?