Allow console option parsers to be merged/combined.
Correct doc block.
Simplify code.
Allow buildFromArray() to not set defaults.
Remove undocumented true param.
Correct attribute.
Avoid arguments piling up by using the latest one given.
Merge branch '3.0' of git://github.com/cakephp/cakephp into 3.0-console-option-parser-merge

Conflicts:
	src/Console/ConsoleOptionParser.php
Check arguments.
Merge pull request #5235 from cakephp/3.0-console-option-parser-merge

3.0: Make console option parsers mergable/combinable