try packaging snap but fail

snapcraft.yaml

@@ -0,0 +1,57 @@
+name: vnote
+version: "2.3"
+summary: Markdown note-taking app
+description: |
+    VNote is a note-taking application that
+    knows programmers and Markdown better.
+    It's designed to provide both powerful
+    note management and pleasant Markdown
+    experience.
+
+confinement: devmode
+
+apps:
+    vnote:
+        command: desktop-launch VNote
+
+parts:
+    vnote:
+        source: https://github.com/tamlok/vnote.git
+        plugin: qmake
+        qt-version: qt5
+        options:
+            - CONFIG+=release
+            - CONFIG+=c++11
+            - CONFIG+=c99
+            - QMAKE_CXX=g++-6
+            - QMAKE_CC=gcc-6
+            - QMAKE_CFLAGS+=-std=c99
+            - ./VNote.pro
+        build-packages:
+            - build-essential
+            - g++-6
+            - gcc-6
+            - qtbase5-dev
+            - libqt5svg5-dev
+            - libqt5webchannel5-dev
+            - qt5-default
+            - qtpositioning5-dev
+            - qtwebengine5-dev
+            - libxcb1-dev
+            - libxcb-xkb-dev
+            - libssl-dev
+            - libgl1-mesa-dev
+        stage-packages:
+            - libqt5gui5
+            - libqt5core5a
+            - libqt5network5
+            - libqt5printsupport5
+            - libqt5webchannel5
+            - libqt5webenginecore5
+            - libqt5webenginewidgets5
+            - libqt5widgets5
+            - libqt5svg5
+            - libxcb1
+            - libxcb-xkb1
+            - openssl
+        after: [desktop-qt5]