Add tests/all.trs to .gitignore

tests/all.trs is auto generated during make check.

Signed-off-by: Nicolas Williams <nico@cryptonector.com>
Fix invalid YAML in manual.yml

Grave accent "`" is a reserved indicator in YAML per
http://www.yaml.org/spec/1.2/spec.html#id2774228, so it can't start a
plain scalar. This commit applies quoting to titles beginning with
grave accents.

Signed-off-by: Nicolas Williams <nico@cryptonector.com>