Upgraded travis CI os

.travis.yml

@@ -1,25 +1,12 @@
 language: cpp
 sudo: required
-dist: bionic
-matrix:
-  include:
-    - os: linux
-      addons:
-        apt:
-          sources:
-            - ubuntu-toolchain-r-test
-          packages:
-            - g++-9
-      env:
-        - MATRIX_EVAL="CC=gcc-9 && CXX=g++-9"
-      compiler:
-        - gcc
+dist: focal
 before_install:
 - eval "${MATRIX_EVAL}"
 - sudo apt-get install build-essential cmake libboost-all-dev libconfig++-dev libavcodec-dev libavutil-dev libavformat-dev ffmpeg libgraphicsmagick++1-dev libpstreams-dev libconfig++-dev libpstreams-dev libtag1-dev libpam0g-dev
 - git clone https://github.com/emweb/wt.git wt
 - pushd wt;
-- git checkout 4.2.1
+- git checkout 4.4.0
 - cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/usr && sudo make install
 - popd
 script: cmake -DCMAKE_BUILD_TYPE=Release . && make && make test