mention linux snap binary in README file

1.2.3

Trivial release to make sure binaries are included in the release.

new release 1.3.1

There was some user confusion about the migration to Gmail, as
evidenced by issues denysdovhan#93 and denysdovhan#95.
This release adds a dialog on startup to explain things.

new release 1.2.2

Backport all fixes and features from v1.3.0 to work on Inbox.
This version is still based on Inbox.

All 1.2.x versions will keep working with Inbox until Google
pulls the plug.

We display a dialog on startup explaining the Inbox situation
to the user.

1.3.0

New version that works with Gmail

1.2.1

1.2.0

1.1.5

1.1.4