Command line Berlin clock (mengenlehreuhr) class implementation.

Supports 24 hours (instead of usual 25). Outputs a mengenlehreuhr string in format:
X-OOOO-OOOO-OOOOOOOOOOO-OOOO.

Which means:
ON/OFF - Hours (5 for each X) - Hours - Minutes (5 for each X) - Minutes

Usage:

bundle
ruby mengenlehreuhr.rb (outputs string for current time)
rspec mengenlehreuhr_spec.rb (runs the tests)