Reduced strictness of rails and sqlite3 dependencies.

Author: umairsiddique

sendable_rails.gemspec

@@ -16,6 +16,6 @@ Gem::Specification.new do |s|
 
   s.files = Dir["{app,config,db,lib}/**/*", "MIT-LICENSE", "Rakefile", "README.md"]
 
-  s.add_development_dependency "rails", "~> 5.1.3"
-  s.add_development_dependency "sqlite3"
+  s.add_development_dependency 'rails', '~> 5.1', '>= 5.1.3'
+  s.add_development_dependency 'sqlite3', '~> 0'
 end