upgrade travis.yml

Author: splitice

.travis.yml

@@ -1,17 +1,14 @@
-language: c
-
+language: csharp
+dist: trusty
+mono:
+  - latest
 git:
   depth: 300
-
-install:
-  - sudo add-apt-repository ppa:directhex/ppa -y
-  - sudo apt-get update
-  - sudo apt-get -qq install mono-devel mono-gmcs mono-utils mono-complete libmono-system2.0-cil libmono-corlib2.0-cil mono-2.0-gac nunit-console realpath
 
 script:
   - bash travis-ci/autoversion.sh QuadTrees
   - export EnableNuGetPackageRestore=false
-  - mozroots --import --sync
+  - cert-sync /etc/ssl/certs/ca-certificates.crt
   - xbuild CI.proj
   - sudo nunit-console -framework=4.0 ./QuadTrees.Tests/bin/Debug/QuadTrees.Tests.dll -exclude Integration,NotWorkingOnMono
   - travis_retry bash travis-ci/nuget-upload.sh