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

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

"git log --decorate" did not reset colors correctly around the
branch names.

* 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