[docs] document the new package release process

Makefile

@@ -46,6 +46,7 @@ depends:
 
 dependsLinux:
 	@sudo apt install libgtk-3-dev libappindicator3-dev golang pkg-config dh-golang golang-golang-x-text-dev cmake devscripts fakeroot debhelper curl
+	@make -C docker deps
 	@# debian needs also: snap install snapcraft --classic; snap install  multipass --beta --classic
 
 dependsDarwin:

docs/release-howto.rst

+how to make a release
+=====================
+1. Tag the release
+2. Build the latest builder image:
+
+```
+make builder_image
+```
+
+3. Build the snap package:
+
+With everything ready on the docker image, this one should be built "in a snap"
+(badum-tsss).
+
+```
+make package_snap_in_docker
+```
+
+4. Build the windows installer:
+
+This is a bit complicated, since it is a two-stage build. It will need you have
+cloned the secrets folder containing the windows authenticode. You also have to
+have wine (32 bits) installed in your host machine.
+
+```
+make package_win_in_docker
+```
+
+5. Build the OSX package: 
+
+(TBD)
+
+6. Build the debian package:
+
+(TBD)