Remove LibSass git submdule from CI

.travis.yml

@@ -36,7 +36,6 @@ addons:
       - g++-4.7
 
 before_install:
-  - git submodule update --init --recursive
   - npm config set python `which python`
   - if [ $TRAVIS_OS_NAME == "linux" ]; then
       export CC="gcc-4.7";

appveyor.yml

@@ -49,7 +49,6 @@
     - ps: Install-Product node $env:nodejs_version $env:platform
     - node --version
     - npm --version
-    - git submodule update --init --recursive
     - npm install --msvs_version=2013
 
   test: off
@@ -121,7 +120,6 @@
     - ps: Install-Product node $env:nodejs_version $env:platform
     - node --version
     - npm --version
-    - git submodule update --init --recursive
     - npm install --msvs_version=2013
 
   test_script: