Add /wup command
The `/wup` command selects a tab by the prefix of its name only. The `/win` will do a substring match based on the first tab going from the current tab which matches the substring. This can be confusing, especially since `/win` matches on different types of tab "names" not only on the name which is shown in the info bar by default. The `/wup` command exclusively matches based on the prefix of the tab.name string. This has the advantage that it is consistent, deterministic and independent of the currently selected tab.