README.md in multi_range-2.1.1 vs README.md in multi_range-2.2.0

@@ -6,12 +6,13 @@
 [![Code Climate](https://codeclimate.com/github/khiav223577/multi_range/badges/gpa.svg)](https://codeclimate.com/github/khiav223577/multi_range)
 [![Test Coverage](https://codeclimate.com/github/khiav223577/multi_range/badges/coverage.svg)](https://codeclimate.com/github/khiav223577/multi_range/coverage)
 
 ## Supports
  
-- Ruby 2.0 ~ 2.7
+- Ruby 2.3 ~ 2.7
 
 For Ruby 1.8.x and 1.9.x, please use multi_range < 2.
+For Ruby 2.0 ~ 2.2, please use multi_range <= 2.1.
 
 ## Installation
 
 ```ruby
 gem 'multi_range'