Drop CicleCI config

.circleci/config.yml

@@ -1,37 +0,0 @@
-version: 2.1
-jobs:
-
-  build_gcc_6:
-    docker:
-      - image: gcc:6
-    steps:
-      - checkout
-      - run: c++ --version
-      - run: make all -j 2
-      - run: ./exprtk_test
-
-  build_gcc_7:
-    docker:
-      - image: gcc:7
-    steps:
-      - checkout
-      - run: c++ --version
-      - run: make all -j 2
-      - run: ./exprtk_test
-
-  build_gcc_latest:
-    docker:
-      - image: gcc:latest
-    steps:
-      - checkout
-      - run: c++ --version
-      - run: make all -j 2
-      - run: ./exprtk_test
-
-workflows:
-  version: 2
-  build_and_test:
-    jobs:
-      - build_gcc_6
-      - build_gcc_7
-      - build_gcc_latest