Fix `undefined method blank?'

[ukstudio]

• require active_support/core_ext for blank? method
• https://github.com/dashofcode/tracker_api/blob/v0.2.8/lib/tracker_api/client.rb#L189

Other fix method.

- if (method == :post || method == :put) && options[:body].blank?
+ if (method == :post || method == :put) && (options[:body].nil? || options[:body].empty?)

[coveralls]

Coverage increased (+0.0%) to 98.28% when pulling d754054 on ukstudio:require_active_support_core_ext into c411bb2 on dashofcode:master.

[coveralls]

Coverage increased (+0.0%) to 98.28% when pulling d754054 on ukstudio:require_active_support_core_ext into c411bb2 on dashofcode:master.

[forest]

Thanks. blank? is one of those methods I always forget isn't core Ruby. Too much Rails development.