Updated snap packaging and fixed version name for appimage

[deepsidhu1313]

• Updated snap packaging yaml to use latest standards
• Fixing version in name of appimage build from travis

[justinclift]

Eyeballing the changes so far, everything seems pretty straight forward. 😄

As it's building from the master branch, I'm guessing this snap will be automatically recreated every time there's a change to it? Like we're doing for our "continuous" release branch these days:

https://github.com/sqlitebrowser/sqlitebrowser/releases/tag/continuous

[deepsidhu1313]

Eyeballing the changes so far, everything seems pretty straight forward. 😄

As it's building from the master branch, I'm guessing this snap will be automatically recreated every time there's a change to it? Like we're doing for our "continuous" release branch these days:

https://github.com/sqlitebrowser/sqlitebrowser/releases/tag/continuous

Snap packages gets pushed automatically to snap store here: https://snapcraft.io/sqlitebrowser