delete snap file

we don't distribute snaps; not sure if the file is useful for anyone
it's already not working because it references python 3.5

snap/snapcraft.yaml

@@ -1,23 +0,0 @@
-name: electrum
-version: master
-summary: Bitcoin thin client
-description: |
-  Lightweight Bitcoin client
-
-grade: devel # must be 'stable' to release into candidate/stable channels
-confinement: strict
-
-apps:
-  electrum:
-    command: desktop-launch electrum
-    plugs: [network, network-bind, x11, unity7]
-
-parts:
-  electrum:
-    source: .
-    plugin: python
-    python-version: python3
-    stage-packages: [python3-pyqt5]
-    build-packages: [pyqt5-dev-tools]
-    install: pyrcc5 icons.qrc -o $SNAPCRAFT_PART_INSTALL/lib/python3.5/site-packages/electrum/gui/qt/icons_rc.py
-    after: [desktop-qt5]