Add license to gemspec.
Add license to gemspec.

bitgal/typhoeus,tinfoil/typhoeus,t3hpr1m3/typhoeus,telekomatrix/typhoeus,AvnerCohen/typhoeus,PericlesTheo/typhoeus,sportngin/typhoeus,typhoeus/typhoeus,wcmonty/typhoeus,tompscanlan/typhoeus,kkirsche/typhoeus,nevans/typhoeus,nju520/typhoeus,EddyLuten/typhoeus,pravi/typhoeus