Appveyor: Problem with dependencies

XMLBear is skipped on Appveyor Windows builds.
This installs dependencies for lxml.

Fixes coala#1354

.ci/appveyor.yml

@@ -49,7 +49,8 @@ install:
   - "%CMD_IN_ENV% pip wheel --use-wheel --wheel-dir C:\\wheels --find-links C:\\wheels -r test-requirements.txt"
   - "%CMD_IN_ENV% pip wheel --use-wheel --wheel-dir C:\\wheels --find-links C:\\wheels -r requirements.txt"
   - "%CMD_IN_ENV% pip install --find-links=C:\\wheels -r test-requirements.txt"
-  - "%CMD_IN_ENV% pip install --find-links=C:\\wheels -r requirements.txt"
+  - "%CMD_IN_ENV% set pip install --find-links=C:\\wheels -r requirements.txt"
+  - "%CMD_IN_ENV% easy_install lxml-3.2.1.win32-py3.3.‌exe"
   - "CALL .ci/deps.nltk.cmd"
 
   - ps: "Install-Product node ''"  # Use latest node v5.x.x