Add ubuntu screenshot and appdata.xml

for #12

.travis.yml

@@ -62,10 +62,13 @@ script:
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then make CXX="g++-4.9 -fext-numeric-literals" || travis_terminate 1; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$(pwd)/thirdparty/meshlite || travis_terminate 1; fi
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then mv dust3d.app dust3d_unstable.app || travis_terminate 1; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mkdir dust3d_unstable || travis_terminate 1; fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mv ./dust3d dust3d_unstable/dust3d_unstable || travis_terminate 1;fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mv ./ci/icon.png dust3d_unstable/icon.png || travis_terminate 1;fi
-  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mv ./ci/dust3d.desktop dust3d_unstable/dust3d.desktop || travis_terminate 1;fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mkdir -p dust3d_unstable/usr/share/metainfo || travis_terminate 1; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mkdir dust3d_unstable/usr/share/applications || travis_terminate 1; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mv ./dust3d dust3d_unstable/dust3d_unstable || travis_terminate 1; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mv ./ci/icon.png dust3d_unstable/icon.png || travis_terminate 1; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then mv ./ci/org.dust3d.appdata.xml dust3d_unstable/usr/share/metainfo/org.dust3d.appdata.xml || travis_terminate 1; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then cp ./ci/org.dust3d.desktop dust3d_unstable/usr/share/applications/org.dust3d.desktop || travis_terminate 1; fi
+  - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then cp ./ci/org.dust3d.desktop dust3d_unstable/org.dust3d.desktop || travis_terminate 1; fi
   - if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then macdeployqt dust3d_unstable.app -dmg || travis_terminate 1; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then chmod a+x ./ci/linuxdeployqt.AppImage || travis_terminate 1; fi
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then ./ci/linuxdeployqt.AppImage dust3d_unstable/dust3d_unstable -appimage -bundle-non-qt-libs -verbose=2 || travis_terminate 1; fi

ci/org.dust3d.appdata.xml

@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<component type="desktop-application">
+​  <id>org.dust3d.desktop</id>
+​  <metadata_license>FSFAP</metadata_license>
+​  <project_license>MIT</project_license>
+​  <name>Dust3D</name>
+​  <summary>A quick 3D modeling tool</summary>
+​
+​  <description>
+​    <p>
+​      Dust3D is a brand new 3D modeling software. It helps you create a 3D watertight base model in seconds. Use it to speed up your character modeling in game making, 3D printing, and so on.
+​    </p>
+​  </description>
+​
+​  <screenshots>
+​    <screenshot type="default">
+​      <caption>Dust3D main window</caption>
+​      <image>https://raw.githubusercontent.com/huxingyi/dust3d/master/ci/screenshot.png</image>
+​    </screenshot>
+​  </screenshots>
+​
+​  <url type="homepage">https://github.com/huxingyi/dust3d</url>
+  <url type="bugtracker">https://github.com/huxingyi/dust3d/issues</url>
+  <url type="help">http://docs.dust3d.org/</url>
+​
+​</component>