Update ups.gemspec

Author: mikefranken

ups.gemspec

@@ -18,7 +18,7 @@ Gem::Specification.new do |gem|
   gem.add_runtime_dependency 'ox', '~> 2.2', '>= 2.2.0'
   gem.add_runtime_dependency 'excon', '~> 0.45', '>= 0.45.3'
   gem.add_runtime_dependency 'insensitive_hash', '~> 0.3.3'
-  gem.add_runtime_dependency 'levenshtein-ffi', '~> 1.1'
+  gem.add_runtime_dependency 'levenshtein-ffi', '~> 1.1', git: "https://github.com/zilverline/levenshtein-ffi.git"
 
   gem.files        = `git ls-files`.split($OUTPUT_RECORD_SEPARATOR)
   gem.require_path = 'lib'