Fix several rubocop issues with "rubocop -a"

lib/homesick/actions.rb

@@ -9,7 +9,7 @@ class Homesick
       destination = Pathname.new(destination) unless destination.kind_of?(Pathname)
       FileUtils.mkdir_p destination.dirname
 
-      if ! destination.directory?
+      if !destination.directory?
         say_status 'git clone', "#{repo} to #{destination.expand_path}", :green unless options[:quiet]
         system "git clone -q --config push.default=upstream --recursive #{repo} #{destination}" unless options[:pretend]
       else
@@ -78,12 +78,12 @@ class Homesick
 
     def git_status(config = {})
       say_status 'git status', '', :green unless options[:quiet]
-      system "git status" unless options[:pretend]
+      system 'git status' unless options[:pretend]
     end
 
     def git_diff(config = {})
       say_status 'git diff', '', :green unless options[:quiet]
-      system "git diff" unless options[:pretend]
+      system 'git diff' unless options[:pretend]
     end
 
     def mv(source, destination, config = {})

lib/homesick/shell.rb

@@ -1,7 +1,6 @@
 class Homesick
   # Hack in support for diffing symlinks
   class Shell < Thor::Shell::Color
-
     def show_diff(destination, content)
       destination = Pathname.new(destination)
 
@@ -12,6 +11,5 @@ class Homesick
         super
       end
     end
-
   end
 end