Update development dependency versions

fabrication.gemspec

@@ -19,13 +19,13 @@ Gem::Specification.new do |s|
   s.rubygems_version = "1.3.7"
   s.summary = "Fabrication provides a robust solution for test object generation."
 
-  s.add_development_dependency("rspec",        [">= 2.4.0"])
-  s.add_development_dependency("cucumber",     [">= 0.10.0"])
-  s.add_development_dependency("ffaker",       [">= 0.4.0"])
-  s.add_development_dependency("activerecord", [">= 3.0.3"])
-  s.add_development_dependency("sqlite3-ruby", ["= 1.3.1"])
-  s.add_development_dependency("bson_ext",     [">=1.2.0"])
-  s.add_development_dependency("mongoid",      ["2.0.0.rc.6"])
-  s.add_development_dependency("sequel",       ["3.16.0"])
+  s.add_development_dependency("rspec",        ["~> 2.5.0"])
+  s.add_development_dependency("cucumber",     ["~> 0.10.2"])
+  s.add_development_dependency("ffaker",       ["~> 1.4.0"])
+  s.add_development_dependency("activerecord", ["~> 3.0.5"])
+  s.add_development_dependency("sqlite3-ruby", ["~> 1.3.3"])
+  s.add_development_dependency("bson_ext",     ["~> 1.2.4"])
+  s.add_development_dependency("mongoid",      ["~> 2.0.0.rc.7"])
+  s.add_development_dependency("sequel",       ["~> 3.21.0"])
   s.add_development_dependency("rake",         ["~> 0.8.7"])
 end