AppveyorCI: Prevent skip of tests of XMLBear

XMLBear is skipped on Appveyor Windows builds
due to dependency issues. Fixes all dependency
issues.

Closes coala#1354

.ci/appveyor.yml

@@ -29,7 +29,7 @@ install:
   # Prepend newly installed Python to the PATH of this build (this cannot be
   # done from inside the powershell script as it would require to restart
   # the parent CMD process).
-  - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
+  - "SET PATH=C:\\tools\\xmllint\\bin;%PYTHON%;%PYTHON%\\Scripts;%PATH%"
   - "SET PATH=C:\\Program\ Files\\Java\\jdk1.7.0\\bin;%PATH%"
 
   # language-tool needs the registry tweaked here since it determines the java
@@ -56,6 +56,15 @@ install:
   - "npm config set loglevel warn"
   - "npm install"
 
+  - curl -fsSL ftp://ftp.zlatkovic.com/libxml/iconv-1.9.2.win32.zip -o iconv.zip
+  - 7z x iconv.zip -oC:\tools\xmllint
+  - curl -fsSL ftp://ftp.zlatkovic.com/libxml/libxml2-2.7.8.win32.zip -o libxml2.zip
+  - 7z x libxml2.zip -oC:\tools\xmllint
+  - curl -fsSL ftp://ftp.zlatkovic.com/libxml/libxslt-1.1.26.win32.zip -o libxslt.zip
+  - 7z x libxslt.zip -oC:\tools\xmllint
+  - curl -fsSL ftp://ftp.zlatkovic.com/libxml/zlib-1.2.5.win32.zip -o zlib.zip
+  - 7z x zlib.zip -oC:\tools\xmllint
+
 build: false  # Not a C# project, build stuff at the test step instead.
 
 test_script: