Remove deprecation warnings

Some good points were made by @jonleighton and @myronmarston in #36
following the 1.3 release. While some or all of these aliased methods
may still be removed or deprecated in version 2, it doesn't seem right
to subject users of libraries that depend on multi_json to deprecation
warnings that they can't do anything about.

Author: sferik

lib/multi_json.rb

@@ -19,12 +19,6 @@ def initialize(message, backtrace, data)
     ["json/pure", :json_pure]
   ]
 
-  # TODO: Remove for 2.0 release (but no sooner)
-  def default_engine
-    deprecate("MultiJson.default_engine is deprecated and will be removed in the next major version. Use MultiJson.default_adapter instead.")
-    self.default_adapter
-  end
-
   # The default adapter based on what you currently
   # have loaded and installed. First checks to see
   # if any adapters are already loaded, then checks
@@ -46,25 +40,17 @@ def default_adapter
     Kernel.warn "[WARNING] MultiJson is using the default adapter (ok_json). We recommend loading a different JSON library to improve performance."
     :ok_json
   end
-
-  # TODO: Remove for 2.0 release (but no sooner)
-  def engine
-    deprecate("MultiJson.engine is deprecated and will be removed in the next major version. Use MultiJson.adapter instead.")
-    self.adapter
-  end
+  # :nodoc:
+  alias :default_engine :default_adapter
 
   # Get the current adapter class.
   def adapter
     return @adapter if @adapter
     self.use self.default_adapter
     @adapter
   end
-
-  # TODO: Remove for 2.0 release (but no sooner)
-  def engine=(new_engine)
-    deprecate("MultiJson.engine= is deprecated and will be removed in the next major version. Use MultiJson.use instead.")
-    self.use(new_engine)
-  end
+  # :nodoc:
+  alias :engine :adapter
 
   # Set the JSON parser utilizing a symbol, string, or class.
   # Supported by default are:
@@ -79,6 +65,8 @@ def use(new_adapter)
     @adapter = load_adapter(new_adapter)
   end
   alias :adapter= :use
+  # :nodoc:
+  alias :engine= :use
 
   def load_adapter(new_adapter)
     case new_adapter
@@ -94,12 +82,6 @@ def load_adapter(new_adapter)
     end
   end
 
-  # TODO: Remove for 2.0 release (but no sooner)
-  def decode(string, options={})
-    deprecate("MultiJson.decode is deprecated and will be removed in the next major version. Use MultiJson.load instead.")
-    self.load(string, options)
-  end
-
   # Decode a JSON string into Ruby.
   #
   # <b>Options</b>
@@ -112,6 +94,8 @@ def load(string, options={})
   rescue adapter::ParseError => exception
     raise DecodeError.new(exception.message, exception.backtrace, string)
   end
+  # :nodoc:
+  alias :decode :load
 
   def current_adapter(options)
     if new_adapter = (options || {}).delete(:adapter)
@@ -121,25 +105,12 @@ def current_adapter(options)
     end
   end
 
-  # TODO: Remove for 2.0 release (but no sooner)
-  def encode(object, options={})
-    deprecate("MultiJson.encode is deprecated and will be removed in the next major version. Use MultiJson.dump instead.")
-    self.dump(object, options)
-  end
-
   # Encodes a Ruby object as JSON.
   def dump(object, options={})
     adapter = current_adapter(options)
     adapter.dump(object, options)
   end
+  # :nodoc:
+  alias :encode :dump
 
-  # Sends of a deprecation warning
-  def deprecate(raw_message)
-    @messages ||= {}
-    message = "#{Kernel.caller[1]}: [DEPRECATION] #{raw_message}"
-    unless @messages[message]
-      @messages[message] = true
-      Kernel.warn message
-    end
-  end
 end

multi_json.gemspec

@@ -13,26 +13,6 @@ Gem::Specification.new do |gem|
   gem.files = Dir['LICENSE.md', 'README.md', 'Rakefile', 'multi_json.gemspec', 'Gemfile', '.document', '.rspec', '.travis.yml' ,'spec/**/*', 'lib/**/*']
   gem.homepage = 'http://github.com/intridea/multi_json'
   gem.name = 'multi_json'
-  gem.post_install_message =<<eos
-********************************************************************************
-
-  MultiJson.encode is deprecated and will be removed in the next major version.
-  Use MultiJson.dump instead.
-
-  MultiJson.decode is deprecated and will be removed in the next major version.
-  Use MultiJson.load instead.
-
-  MultiJson.engine is deprecated and will be removed in the next major version.
-  Use MultiJson.adapter instead.
-
-  MultiJson.engine= is deprecated and will be removed in the next major
-  version. Use MultiJson.use instead.
-
-  MultiJson.default_engine is deprecated and will be removed in the next major
-  version. Use MultiJson.default_adapter instead.
-
-********************************************************************************
-eos
   gem.rdoc_options = ["--charset=UTF-8"]
   gem.require_paths = ['lib']
   gem.required_rubygems_version = Gem::Requirement.new(">= 1.3.6")