test: add language agnostic toml-test

.circleci/config.yml

@@ -0,0 +1,24 @@
+version: 2.1
+
+jobs:
+  test:
+    docker:
+      - image: circleci/buildpack-deps:bionic
+    steps:
+      - checkout
+      - run: g++ --version
+      - run: cd test/
+      - run: g++ -std=c++11 -O2 -Wall -Wextra -Werror check.cpp -o check
+      - run: git clone https://github.com/BurntSushi/toml-test.git
+      - run: cp check toml-test/tests/invalid
+      - run: cp check toml-test/tests/valid
+      - run: cd toml-test/tests/invalid
+      - run: for f in $(ls ./*.toml); do echo "==> ${f}"; cat ${f}; ./check ${f} invalid; done
+      - run: cd ../valid
+      - run: for f in $(ls ./*.toml); do echo "==> ${f}"; cat ${f}; ./check ${f} valid; done
+
+workflows:
+  version: 2.1
+  test:
+    jobs:
+      - test