Allow nil values in float type.
Merge pull request #8 from tiramizoo/allow_nil_floats

Allow nil values in float type.
gitignored coverage
added codeclimate, gemnasium and coverage
added fury badge
new json gem dependency in gemspec
pulled lines into separate files
added comments to clarify the parsing of lines
new demo login data
refactored api line
refactored Collmex::Api.parse_line
refactored Collmex::Api::Line