Do shorten long branch names in journal/log

Long branch names push the commit message out of the view. Shorten long branch names so at least a part of the commit message is visible.

A example for a long branch name:

custom/JDK8/dr-21654-some-jira-issue-title

Depending on the available space, shortening could be more aggressive. Everything from
custom/JDK8/dr-...jira-issue-title
to
cust...itle

could be possible.

The main aim should be to leave some space for the commit message.