update Gemfile to address build issues with 1.9.1

Gemfile

@@ -14,21 +14,23 @@ end
 gem "rake", "0.8.7"
 gem "cucumber", "~> 0.10.2"
 gem "aruba", "~> 0.3.5"
-gem "rcov", "0.9.9"
+gem "rcov", "0.9.9", :platforms => :mri
 gem "relish", "0.2.0"
 gem "guard-rspec", "0.1.9"
 gem "growl", "1.0.3"
-gem "ZenTest", "~> 4.4.2"
+gem "nokogiri", "1.4.4"
 
-if RUBY_PLATFORM =~ /darwin/
-  gem "autotest-fsevent", "~> 0.2.4"
-  gem "autotest-growl", "~> 0.2.9"
+platforms :mri_18 do
+  gem 'ruby-debug'
 end
 
-gem "ruby-debug", :platforms => :ruby_18
-gem "ruby-debug19", "~> 0.11.6", :platforms => :ruby_19
+platforms :mri_19 do
+  gem 'linecache19', '0.5.11' # 0.5.12 cannot install on 1.9.1, and 0.5.11 appears to work with both 1.9.1 & 1.9.2
+  gem 'ruby-debug19'
+  gem 'ruby-debug-base19', RUBY_VERSION == '1.9.1' ? '0.11.23' : '~> 0.11.24'
+end
 
-platforms :ruby_18, :ruby_19 do
+platforms :mri_18, :mri_19 do
   gem "rb-fsevent", "~> 0.3.9"
   gem "ruby-prof", "~> 0.9.2"
 end