Try PGF90 compiler on Travis

Can we build and run our tests with PGI's
community compiler? Using:
    https://github.com/nemequ/pgi-travis

Author: andreww

.travis.yml

@@ -34,6 +34,10 @@ env:
       BUILD_SCRIPT="FC='ifort -notraceback' ./configure &&
       make -j 2 && make -j 2 check && ./testcheck.sh" COMPILER="ifort"
 
+      # Using configure and make and pgi run the tests.
+    - >
+      BUILD_SCRIPT="FC='pgf90' ./configure &&
+      make -j 2 && make -j 2 check && ./testcheck.sh" COMPILER="pgi"
 
 install:
   - |
@@ -51,6 +55,11 @@ install:
       chmod u+x ./install-icc.sh
       ./install-icc.sh --components ifort
       source ~/.bashrc
+    elif [[ "$COMPILER" == 'pgi' ]]; then
+      wget -q 'https://raw.githubusercontent.com/nemequ/pgi-travis/master/install-pgi.sh' 
+      chmod u+x ./install-pgi.sh
+      ./install-pgi.sh 
+      source ~/.bashrc
     fi
 
 script: