update readme badges, remove travis and appveyor

.github/workflows/coverage.yml

@@ -8,7 +8,7 @@ jobs:
     name: "coverage"
     steps:
     - uses: actions/checkout@v2
-    - name: install lcov
+    - name: Install lcov by Homebrew
       run: brew install lcov
-    - name: build
+    - name: Build && Test && Upload
       run: .ci/build_coverage.sh

.github/workflows/darwin.yml

@@ -16,7 +16,7 @@ jobs:
     name: "xcode-${{matrix.config.xcode}}"
     steps:
     - uses: actions/checkout@v2
-    - name: select xcode
+    - name: Select Xcode
       run: sudo xcode-select --switch "/Applications/Xcode_${{matrix.config.xcode}}.app"
-    - name: build
+    - name: Build && Test
       run: .ci/build_darwin.sh

.github/workflows/linux.yml

@@ -20,6 +20,6 @@ jobs:
     name: "${{matrix.config.cxx}}"
     steps:
     - uses: actions/checkout@v2
-    - name: build
+    - name: Build && Test
       run: .ci/build_linux.sh
       env: { CC: "${{matrix.config.cc}}", CXX: "${{matrix.config.cxx}}" }

.github/workflows/windows.yml

@@ -17,5 +17,5 @@ jobs:
     name: "${{matrix.config.vs}}"
     steps:
     - uses: actions/checkout@v2
-    - name: build
+    - name: Build && Test
       run: .ci\build_windows_${{matrix.config.arch}}.bat