Upgrade ffi to 1.9.4, and remove platform conditionals.

Specifying a released version of a gem as requirement wouldn't hurt
other platforms.

Gemfile

@@ -95,20 +95,9 @@ group :production do
   gem 'rack'
 end
 
-case RUBY_PLATFORM
-  when /freebsd|netbsd|openbsd/
-    # ffi (required by typhoeus via ethon) merged fixes for bugs fatal
-    # on these platforms after 1.9.3; no following release as yet.
-    gem 'ffi', github: 'ffi/ffi', branch: 'master'
-
-    # tzinfo 1.2.0 has added support for reading zoneinfo on these
-    # platforms.
-    gem 'tzinfo', '>= 1.2.0'
-  when /solaris/
-    # ditto
-    gem 'tzinfo', '>= 1.2.0'
-end
-
+# Platform requirements.
+gem 'ffi', '>= 1.9.4'		# required by typhoeus; 1.9.4 has fixes for *BSD.
+gem 'tzinfo', '>= 1.2.0'	# required by rails; 1.2.0 has support for *BSD and Solaris.
 # Windows does not have zoneinfo files, so bundle the tzinfo-data gem.
 gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw]
 

Gemfile.lock

@@ -119,7 +119,7 @@ GEM
     feed-normalizer (1.5.2)
       hpricot (>= 0.6)
       simple-rss (>= 1.1)
-    ffi (1.9.3)
+    ffi (1.9.4)
     forecast_io (2.0.0)
       faraday
       hashie
@@ -407,6 +407,7 @@ DEPENDENCIES
   faraday (~> 0.9.0)
   faraday_middleware
   feed-normalizer
+  ffi (>= 1.9.4)
   forecast_io (~> 2.0.0)
   foreman (~> 0.63.0)
   geokit (~> 1.8.4)
@@ -453,6 +454,7 @@ DEPENDENCIES
   twilio-ruby (~> 3.11.5)
   twitter (~> 5.8.0)
   typhoeus (~> 0.6.3)
+  tzinfo (>= 1.2.0)
   tzinfo-data
   uglifier (>= 1.3.0)
   unicorn