Some do not use the json module directly so don't need import json.
Some needed to fallback to simplejson with no traceback if neither was installed
Fixes#1298
pkgin searches for packages such as 'emacs' can return multiple matches,
the first of which is not guaranteed to match. So, iterate through
found packages until we have an appropriate match. Should we *not* find
a match, then return False indicating match failure.
* Add support for check mode
* Use "pkgin search" to guarantee 0 or 1 result
* Edit documentation for style, new feature, etc.
* General refactoring
* Lay some groundwork for future support of "state=latest"
