Install latest .NET CLI packages on Travis

.travis.yml

@@ -10,12 +10,9 @@ git:
 before_install:
   - git config --global url.git@github.com:.insteadOf https://github.com/
   - git submodule update --init --recursive -- src/libpsl-native src/windows-build src/Microsoft.PowerShell.Linux.Host/Modules/Pester
-  - sudo sh -c 'echo "deb [arch=amd64] http://apt-mo.trafficmanager.net/repos/dotnet/ trusty main" > /etc/apt/sources.list.d/dotnetdev.list'
-  - sudo apt-key adv --keyserver apt-mo.trafficmanager.net --recv-keys 417A0893
-  - sudo apt-get -qq update
-  - sudo apt-get install -y dotnet=1.0.0.001675-1
+  - ./bootstrap.sh
   - ./download.sh
-  - sudo dpkg -i powershell.deb
+  - sudo dpkg -i ./powershell.deb
 script:
   - powershell -c "Import-Module ./PowerShellGitHubDev.psm1; Start-PSBuild"
   - ./pester.sh