BUILD: Update Travis CI config to install g++-7 and Qt

.travis.yml

@@ -2,9 +2,6 @@ sudo: required
 dist: trusty
 
 language: cpp
-compiler:
-  - gcc
-  - clang
 
 env:
   global:
@@ -13,23 +10,31 @@ env:
     - secure: "dn5Irr/svB2d/iouvSxxoe2SEAWlPUlkNlGWScngWhqSp+kEJ8p3ubQG0ogCK0vGGHPwUYXfIQvHQ8oSc2Z4na8rIwZqvkJnxYYKvPLZpweKhb+xQbpjPwDwEycFDxT+y7mPnRLKRDtdmcuRqMQh8gnxb6TMY9xqlCCvnTfwTmI="
     - coverity_scan_run_condition='\( "$CC" = gcc \) -a \( $USECMAKE -eq 0 \)'
     - coverity_scan_script_test_mode=false
-  matrix:
-    # Let's test both our autoconf and CMake build system
-    - USECMAKE=0
-    - USECMAKE=1
 
-# Only test clang with autotools, not CMake.
 # We now have three builds: autoconf+gcc, autoconf+clang, CMake+gcc
 matrix:
-  exclude:
+  include:
+    - compiler: gcc
+      env:
+      - USECMAKE=0
+      - COMPILER_EVAL="CXX=g++-7"
+    - compiler: gcc
+      env:
+      - USECMAKE=1
+      - COMPILER_EVAL="CXX=g++-7"
     - compiler: clang
-      env: USECMAKE=1
+      env:
+      - USECMAKE=0
 
 before_script:
-  # The wxWidget version in Trusty won't compile without
-  - export CXXFLAGS="-std=c++0x"
+  - echo "yes" | sudo add-apt-repository "deb http://archive.ubuntu.com/ubuntu xenial main universe restricted multiverse"
+  - echo "yes" | sudo add-apt-repository ppa:ubuntu-toolchain-r/test
+  - sudo apt-get update -qq
+  - sudo apt-get -y -o Dpkg::Options::="--force-confdef" -o Dpkg::Options::="--force-confnew" install g++-7 libboost-all-dev libopenal-dev libmad0-dev libvorbis-dev zlib1g-dev liblzma-dev qtbase5-dev libqt5gui5 libqt5multimedia5 qtmultimedia5-dev libqt5multimediawidgets5
 
 script:
+  # Set the correct compiler
+  - eval "${COMPILER_EVAL}"
   # Configure, autotools
   - if [ \( "$COVERITY_SCAN_BRANCH" != 1 \) -a \( $USECMAKE -eq 0 \) ]; then ./autogen.sh; fi
   - if [ \( "$COVERITY_SCAN_BRANCH" != 1 \) -a \( $USECMAKE -eq 0 \) ]; then ./configure || cat config.log; fi
@@ -43,17 +48,6 @@ script:
   - if [ \( "$COVERITY_SCAN_BRANCH" != 1 \) -a \( $USECMAKE -eq 1 \) ]; then make -j4 check; fi
 
 addons:
-  apt:
-    packages:
-      - libboost-all-dev
-      - libopenal-dev
-      - libmad0-dev
-      - libvorbis-dev
-      - zlib1g-dev
-      - liblzma-dev
-      - libwxgtk3.0-dev
-      - libpango-1.0-0
-      - libpangocairo-1.0-0
   coverity_scan:
     build_script_url: https://raw.githubusercontent.com/$TRAVIS_REPO_SLUG/$TRAVIS_BRANCH/.travis_coverity.sh
     project: