Unable to merge via curation siderbar if username contains "."

[reckart]

Describe the bug
If the username of an annotator contains special characters, their annotation cannot be merged anymore.

The problem is the VID encoding used by the curation sidebar as well as the regular expression used to parse it. The regex does not consider all characters possible in a user name. The VID encoding does neither escape the username or use a character that cannot occur in a username as a separator between username and payload. It uses ":" as a separator which can occur in a username.

To Reproduce
Steps to reproduce the behavior:

1. Create a user "john.smith"
2. Make annotations with the user
3. Open the annotation page and the curation sidebar
4. Try to merge an annotation from user "john.smith"

Expected behavior
Should just work.

Please complete the following information:

• Version and build ID: 0.18.3