Migrate to GitHub actions (palicao#24)

* Create main Github action

* add psalm step in github action and remove travis

Author: palicao

.github/workflows/main.yml

@@ -0,0 +1,57 @@
+name: CI
+
+# Controls when the action will run. 
+on:
+  # Triggers the workflow on push or pull request events but only for the master branch
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  build:
+    name: PHP ${{ matrix.php-versions }} - RedisTimeSeries ${{ matrix.rts-versions }}
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        php-versions: ['7.2', '7.3', '7.4']
+        rts-versions: ['1.4.8', 'edge']
+    services:
+      redis:
+        image: redislabs/redistimeseries:${{ matrix.rts-versions }}
+        ports: 
+          - 6379:6379
+        options: --health-cmd="redis-cli ping" --health-interval=10s --health-timeout=5s --health-retries=3
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Setup PHP
+        uses: shivammathur/setup-php@v2
+        with:
+          php-version: ${{ matrix.php-versions }}
+          extensions: redis
+          coverage: xdebug
+      - name: Get composer cache directory
+        id: composer-cache
+        run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+      - name: Cache composer dependencies
+        uses: actions/cache@v2
+        with:
+          path: ${{ steps.composer-cache.outputs.dir }}
+          # Use composer.json for key, if composer.lock is not committed.
+          # key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.json') }}
+          key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
+          restore-keys: ${{ runner.os }}-composer-
+      - name: Install dependencies
+        run: |
+          composer install --no-progress --prefer-dist --optimize-autoloader
+      - name: Run tests
+        run: vendor/bin/phpunit --coverage-text
+        env:
+          REDIS_HOST: localhost
+          REDIS_TIMESERIES_VERSION: ${{ matrix.rts-versions }}
+      - name: Run psalm
+        run: vendor/bin/psalm