Merge branch 'rr/for-each-ref-decoration'

Add a few formatting directives to "git for-each-ref --format=...", to paint them in color, etc. * rr/for-each-ref-decoration: for-each-ref: avoid color leakage for-each-ref: introduce %(color:...) for color for-each-ref: introduce %(upstream:track[short]) for-each-ref: introduce %(HEAD) asterisk marker t6300 (for-each-ref): don't hardcode SHA-1 hexes t6300 (for-each-ref): clearly demarcate setup