Fix #15
Make #each more efficient
Remove unnecessary sorting plus cleanups
Make Collection constructor leaner
Fix rubocop issues
Remove unused attr_accessors
Improve readability
Increase version
Fix #16
Increase version
Use single quote strings
Remove code duplication
Update README.md
Improve readability of Collection
using default block in fetch call for TimeFrame#initialize
added arel predicate building capacity for time_frame, added specs
satisfied rubocop