build: added Travis ci for Linux builds (#857)

deployment/dockerfiles/linux/travis_ci/Dockerfile

@@ -0,0 +1,5 @@
+FROM coatisoftware/centos7_64_qt_llvm:qt5126-llvm900
+
+COPY entrypoint.sh /entrypoint.sh
+
+ENTRYPOINT ["/entrypoint.sh"]

deployment/dockerfiles/linux/travis_ci/entrypoint.sh

@@ -0,0 +1,15 @@
+#!/bin/sh -l
+
+echo "building commit: $1"
+
+git clone https://github.com/CoatiSoftware/Sourcetrail.git
+
+cd Sourcetrail
+
+git checkout $1
+
+./script/buildonly.sh all
+
+./script/buildonly.sh package
+
+./script/build.sh release test