Merge branch 'jc/decorate-leaky-separator-color' into HEAD

* jc/decorate-leaky-separator-color: log --decorate: do not leak "commit" color into the next item Documentation/config.txt: simplify boolean description in the syntax section Documentation/config.txt: describe 'color' value type in the "Values" section Documentation/config.txt: have a separate "Values" section Documentation/config.txt: describe the structure first and then meaning Documentation/config.txt: explain multi-valued variables once Documentation/config.txt: avoid unnecessary negation