test Julia 1.3, FreeBSD, add badge

Author: dpo

.appveyor.yml

@@ -3,6 +3,7 @@ environment:
   - julia_version: 1
   - julia_version: 1.1
   - julia_version: 1.2
+  - julia_version: 1.3
   - julia_version: nightly
 
 platform:

.cirrus.yml

@@ -0,0 +1,17 @@
+freebsd_instance:
+  image: freebsd-12-0-release-amd64
+task:
+  name: FreeBSD
+  env:
+    matrix:
+      - JULIA_VERSION: 1.0
+      - JULIA_VERSION: 1.1
+      - JULIA_VERSION: 1.2
+      - JULIA_VERSION: 1.3
+      - JULIA_VERSION: nightly
+  install_script:
+    - sh -c "$(fetch https://raw.githubusercontent.com/ararslan/CirrusCI.jl/master/bin/install.sh -o -)"
+  build_script:
+    - cirrusjl build
+  test_script:
+    - cirrusjl test

README.md

@@ -2,6 +2,7 @@
 
 Linux and macOS: [![Build Status](https://travis-ci.org/JuliaSmoothOptimizers/QuadraticModels.jl.svg?branch=master)](https://travis-ci.org/JuliaSmoothOptimizers/QuadraticModels.jl)
 Windows: [![Build Status](https://ci.appveyor.com/api/projects/status/github/JuliaSmoothOptimizers/QuadraticModels.jl?branch=master&svg=true)](https://ci.appveyor.com/project/tkelman/example-jl/branch/master)
+FreeBSD: [![Build Status](https://api.cirrus-ci.com/github/JuliaSmoothOptimizers/QuadraticModels.jl.svg)](https://cirrus-ci.com/github/JuliaSmoothOptimizers/QuadraticModels.jl)
 [![Coverage Status](https://coveralls.io/repos/JuliaSmoothOptimizers/QuadraticModels.jl/badge.svg?branch=master)](https://coveralls.io/r/JuliaSmoothOptimizers/QuadraticModels.jl?branch=master)
 [![codecov.io](http://codecov.io/github/JuliaSmoothOptimizers/QuadraticModels.jl/coverage.svg?branch=master)](http://codecov.io/github/JuliaSmoothOptimizers/QuadraticModels.jl?branch=master)