Rename YAML::VERSION. It's conflict with Psych::VERSION

lib/yaml.rb

@@ -66,5 +66,5 @@ YAML = Psych # :nodoc:
 #
 # Syck can also be found on github: https://github.com/ruby/syck
 module YAML
-  VERSION = "0.2.1"
+  LOADER_VERSION = "0.2.1"
 end

lib/yaml/yaml.gemspec

@@ -1,7 +1,7 @@
 name = File.basename(__FILE__, ".gemspec")
 version = ["lib", Array.new(name.count("-")+1, "..").join("/")].find do |dir|
   break File.foreach(File.join(__dir__, dir, "#{name.tr('-', '/')}.rb")) do |line|
-    /^\s*VERSION\s*=\s*"(.*)"/ =~ line and break $1
+    /^\s*LOADER_VERSION\s*=\s*"(.*)"/ =~ line and break $1
   end rescue nil
 end