Appveyor: Fix Tests

- Use clean PATH, to not interfere with other programs in the path
- Use forward slashs to not interfere with escaping
- Run tests with --verbose, to get code warnings

appveyor.yml

@@ -1,32 +1,31 @@
 init:
-  - SET PATH=C:\Ruby%ruby_version%\bin;%PATH%
-  - SET PATH=C:\MinGW\msys\1.0\bin;%PATH%
-  - SET RAKEOPT=-rdevkit
+  - set PATH=C:/Ruby%ruby_version%/bin;c:/Program Files/Git/cmd;c:/Windows/system32;C:/Windows/System32/WindowsPowerShell/v1.0
+  - set RUBYOPT=--verbose
 install:
   - ruby --version
   - gem --version
   - bundle install
   - ps: |
       if ($env:PGVERSION -ne $null)
       {
-        $(new-object net.webclient).DownloadFile('http://get.enterprisedb.com/postgresql/postgresql-' + $env:PGVERSION + '.exe', 'C:\postgresql-setup.exe')
-        cmd /c C:\postgresql-setup.exe --mode unattended --extract-only 1
+        $(new-object net.webclient).DownloadFile('http://get.enterprisedb.com/postgresql/postgresql-' + $env:PGVERSION + '.exe', 'C:/postgresql-setup.exe')
+        cmd /c "C:/postgresql-setup.exe" --mode unattended --extract-only 1
       }
-      $env:RUBY_DLL_PATH = 'C:\Program Files\PostgreSQL\' + $env:PGVER + '\bin;C:\Program Files (x86)\PostgreSQL\' + $env:PGVER + '\bin'
-      $env:PATH = 'C:\Program Files\PostgreSQL\' + $env:PGVER + '\bin;' + $env:PATH
-      $env:PATH = 'C:\Program Files (x86)\PostgreSQL\' + $env:PGVER + '\bin;' + $env:PATH
+      $env:RUBY_DLL_PATH = 'C:/Program Files/PostgreSQL/' + $env:PGVER + '/bin;C:/Program Files (x86)/PostgreSQL/' + $env:PGVER + '/bin'
+      $env:PATH = 'C:/Program Files/PostgreSQL/' + $env:PGVER + '/bin;' + $env:PATH
+      $env:PATH = 'C:/Program Files (x86)/PostgreSQL/' + $env:PGVER + '/bin;' + $env:PATH
 build_script:
-  - bundle exec rake compile
+  - bundle exec rake -rdevkit compile
 test_script:
   - bundle exec rake test
 environment:
   matrix:
-    - ruby_version: "24"
-      PGVERSION: 10.0-1-windows
-      PGVER: 10
     - ruby_version: "24-x64"
       PGVERSION: 10.0-1-windows-x64
       PGVER: 10
+    - ruby_version: "24"
+      PGVERSION: 10.0-1-windows
+      PGVER: 10
     - ruby_version: "22"
       PGVERSION: 9.3.19-1-windows
       PGVER: 9.3