adding lazy_high_charts gem, require assets
adding poltergeist driver for capybara
remove highchart stocks
requirement completion chart with dummy data
calculation of incomplete/complete requirements

This commit adds code to help building the data series for the
high_charts helper.
To simplify I created a service class called RequirementSeries which
 receives the Requirement class and a user as attributes.
Leveraging on user<->proofs<->requirements relationships I use the
user proofs count for a given requirement as a base to calculate the
percentage of complete requirements, since a user can submit only 1
 proof per requirement.
To calculate the number and percentage of incomplete requirements I
subtract the number of complete requirements from the total number
of requirements.
move back service object to requirement model
removing klass attribute from RequirementSeries service object
round percentage to 1 decimal
Merge branch 'requirements-progress' of github.com:akshatpradhan/compliance_chimp into requirements-progress

Conflicts:
	app/models/requirement.rb
	app/views/requirements/index.html.erb
	spec/models/requirement_spec.rb