update gemspec

Author: chamnap

liquid-rails.gemspec

@@ -9,9 +9,11 @@ Gem::Specification.new do |spec|
   spec.authors       = ['Chamnap Chhorn']
   spec.email         = ['[email protected]']
   spec.summary       = %q{Renders liquid templates with layout and partial support}
-  spec.description   = %q{Renders liquid templates with layout and partial support}
+  spec.description   = %q{It allows you to render .liquid templates with layout and partial support. It also provides filters, tags, drops class to be used inside your liquid template.}
   spec.homepage      = ''
   spec.license       = 'MIT'
+  spec.required_ruby_version     = '>= 2.0.0'
+  spec.required_rubygems_version = '>= 1.8.11'
 
   spec.files         = `git ls-files -z`.split("\x0")
   spec.executables   = spec.files.grep(%r{^bin/}) { |f| File.basename(f) }