Cherry-pick "Merge branch 'DictionaryDepImprovements-master-20181127' into 'master'" into 2.0.15-patches

Dictionary Dependency Improvements, master branch (2018.12.12.)

See merge request !402 (merged)

(cherry picked from commit b3c2a937)

• 682867c0 Started with some developments to teach Ninja about dictionary dependencies.
• 3d4bf66d Merge remote-tracking branch 'upstream/master' into DictionaryDepImprovements-master-20181127
• 79bc8f74 Added dictionary generation improvements for GNU Make.