Merge branch 'hn/highlight-sideband-keywords'

Lines that begin with a certain keyword that come over the wire, as well as lines that consist only of one of these keywords, ought to be painted in color for easier eyeballing, but the latter was broken ever since the feature was introduced in 2.19, which has been corrected. * hn/highlight-sideband-keywords: sideband: color lines with keyword only