Added first iteration of Travis CI build file.

.travis.yml

@@ -0,0 +1,13 @@
+language: cpp
+
+install:
+  - sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF
+  - echo "deb http://download.mono-project.com/repo/debian wheezy main" | sudo tee /etc/apt/sources.list.d/mono-xamarin.list
+  - sudo apt-get update -qq
+  - sudo apt-get install -qq mono-devel nuget
+  - build/premake5-linux --file=build/premake4.lua gmake
+  - nuget install NUnit.Runners -Version 2.6.4 -OutputDirectory testrunner
+
+script:
+  - config=debug_x32 make -C build/gmake/
+  - mono ./testrunner/NUnit.Runners.2.6.4/tools/nunit-console.exe build/gmake/lib/Debug_x32/CppSharp.*Tests*.dll