Introduce AppVeyor for testing the build on Windows

Author: davehunt

.buckjavaargs

@@ -1 +1 @@
--Xmx2048m -XX:+HeapDumpOnOutOfMemoryError
+-Xmx1g -XX:+HeapDumpOnOutOfMemoryError

appveyor.yml

@@ -0,0 +1,9 @@
+shallow_clone: true
+build: off
+install:
+  - 'set JAVA_HOME=C:\Program Files (x86)\Java\jdk1.8.0'
+  - 'set PATH=%JAVA_HOME%;%PATH%'
+  - 'set RUBY_HOME=C:\Ruby22-x64\bin'
+  - 'set PATH=%RUBY_HOME%;%PATH%'
+test_script:
+  - cmd: './go build'

rake-tasks/buck.rb

@@ -83,7 +83,8 @@ def output
         proc.wait
 
         if proc.exit_code != 0
-          raise "Buck build failed"
+          raise "Buck build failed with exit code: #{proc.exit_code}
+stdout: #{proc.io.stdout.output}"
         end
 
         block.call(proc.io.stdout.output) if block