travis: Implement rot13 with tr(1).

This should work on OSX, and even though grabbing it from the bsdgames
package ought to have worked on Linux, it apparently didn't, so let's
try this instead.

travis-install.sh

@@ -13,7 +13,7 @@ if [ -z ${STACK_CONFIG+x} ]; then
     if [ "$TRAVIS_OS_NAME" = "linux" ]; then
         travis_retry sudo add-apt-repository -y ppa:hvr/ghc
         travis_retry sudo apt-get update
-        travis_retry sudo apt-get install --force-yes cabal-install-head cabal-install-2.0 happy-1.19.5 alex-3.1.7 ghc-$GHCVER-prof ghc-$GHCVER-dyn bsdgames
+        travis_retry sudo apt-get install --force-yes cabal-install-head cabal-install-2.0 happy-1.19.5 alex-3.1.7 ghc-$GHCVER-prof ghc-$GHCVER-dyn
         if [ "x$TEST_OTHER_VERSIONS" = "xYES" ]; then travis_retry sudo apt-get install --force-yes ghc-7.0.4-prof ghc-7.0.4-dyn ghc-7.2.2-prof ghc-7.2.2-dyn ghc-head-prof ghc-head-dyn; fi
 
     elif [ "$TRAVIS_OS_NAME" = "osx" ]; then

travis/upload.sh

@@ -39,7 +39,7 @@ cd travis
 # Setup SSH key we will use to push to binaries repository.
 # umask to get the permissions to be 600 (not 400, because the deploy
 # script in .travis.yml is going to clobber this private key)
-(umask 177 && rot13 < id_rsa.rot13 > $HOME/.ssh/id_rsa)
+(umask 177 && tr A-Z N-ZA-M < id_rsa.rot13 > $HOME/.ssh/id_rsa)
 
 # Setup SSH keys
 ssh-keyscan github.com >> $HOME/.ssh/known_hosts
@@ -65,7 +65,7 @@ mkdir cabal-install
 cp -R $TRAVIS_BUILD_DIR/Cabal/tests                                  Cabal
 cp -R $TRAVIS_BUILD_DIR/cabal-install/tests                          cabal-install
 # Copy in credentials so we can delete branch when done
-rot13 < $TRAVIS_BUILD_DIR/travis/id_rsa.rot13 > id_rsa
+tr A-Z N-ZA-M < $TRAVIS_BUILD_DIR/travis/id_rsa.rot13 > id_rsa
 # Install all of the necessary files for testing
 cp $TRAVIS_BUILD_DIR/travis-install.sh .
 cp $TRAVIS_BUILD_DIR/travis-common.sh .