[fix] Don't have git report deleted files

Saves a for loop that checks if the files were deleted or not - silly
because git already would have known that information.

.travis.yml

@@ -8,11 +8,8 @@ before_script:
   - mkdir -p ~/build
   - git clone --branch hubzero-cms-2.1 --depth=1 https://github.com/hubzero/standards ~/build/standards
   - git config diff.renameLimit 0
-  - changed_files=`git diff --name-only $TRAVIS_COMMIT_RANGE`
-  - for f in $changed_files; do if [[ -f "$f" ]]; then files_exist="$files_exist $f"; else files_removed="$files_removed $f"; fi done
+  - changed_files=`git diff --diff-filter=ACMRTUXB --name-only $TRAVIS_COMMIT_RANGE`
   - echo "The following will be tested:"
-  - echo $files_exist
-  - echo "The following were removed:"
-  - echo $files_removed
+  - echo $changed_files
 script:
-- core/bin/php_tests.sh $files_exist
+- core/bin/php_tests.sh $changed_files