refactor the Promises$reduce state machine
performance improvements the Promises$reduce state machine
PR feedback from @petkaantonov

- REDUCE_PHASE_* constants
- eliminate implicit Boolean type coercion
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Update devDependencies

From JSHint v2.5.0, trailing option and smart tabs option are removed.
Consistently reject with a RangeError when input array contains too few promises. Fixes #233
Release v2.2.0
Support multiline error messages. Fixes #256
Release v2.2.1
Fixes #259
Release v2.2.2