WalletConnect integration issues

[sche]

I used Gnosis Safe iOS app for testing WalletConnect integration.

Disconnect event from a wallet is not handled properly

1. Connect app to rinkeby.gnosis-safe.io via WalletConnect
   => success
2. Disconnect from Gnosis Safe iOS app
   expected result: the wallet is disconnected, the web interface handles disconnect event properly
   actual result:
   a) WalletConnect QR code is displayed (that is not valid anymore)
   b) In UI the wallet is still displayed as connected

Reject response is not handled when creating a safe.

1. Connect a Gnosis Safe mobile app to rinkeby.gnosis-safe.io via WalletConnect
2. Try to create a new safe with 1 owner (mobile app)
3. Reject transaction in Mobile App
   expected result: web interface should handle it
   actual result: nothing happens in the web interface

[mmv08]

This was fixed by #324, but not deployed yet

[mmv08]

You can try the fix on dev env