reintroduced coveralls integration

.travis.yml

@@ -32,7 +32,7 @@ after_success: |
   cd ../.. &&
   rm -rf kcov-master &&
   ls -al target/debug &&
-  for file in target/debug/cionc*; do mkdir -p "target/cov/$(basename $file)"; kcov --exclude-pattern=/.cargo,/usr/lib --verify "target/cov/$(basename $file)" "$file"; done &&
+  for file in target/debug/cionc*; do mkdir -p "target/cov/$(basename $file)"; kcov --coveralls-id=$TRAVIS_JOB_ID --exclude-pattern=/.cargo,/usr/lib --verify "target/cov/$(basename $file)" "$file"; done &&
   bash <(curl -s https://codecov.io/bash) &&
   echo "Uploaded code coverage"