[Command] Don't default `pod` to `pod install`

I'm sure everyone is going to hate me for doing this.

Fixes #1771
Closes #1966

CHANGELOG.md

@@ -20,6 +20,11 @@ To install or update CocoaPods see this [guide](http://docs.cocoapods.org/guides
   [Samuel E. Giddins](https://github.com/segiddins)
   [#2049](https://github.com/CocoaPods/CocoaPods/issues/2049)
 
+* Show `help` when running the `pod` command instead of defaulting to `pod
+  install`.  
+  [Kyle Fuller](https://github.com/kylef)
+  [#1771](https://github.com/CocoaPods/CocoaPods/issues/1771)
+
 ##### Bug Fixes
 
 * Fixed support for file references in the workspace generated by CocoaPods.  

lib/cocoapods/command.rb

@@ -22,7 +22,6 @@ module Pod
     require 'cocoapods/command/init'
 
     self.abstract_command = true
-    self.default_subcommand = 'install'
     self.command = 'pod'
     self.description = 'CocoaPods, the Objective-C library package manager.'
     self.plugin_prefix = 'cocoapods'