Upstream merge 4

[stoffu]

This pull request merges upstream patches after https://github.com/monero-project/monero-gui/pull/1469 which is the last one included in #22. This PR includes upstream PRs from https://github.com/monero-project/monero-gui/pull/1511 up to https://github.com/monero-project/monero-gui/pull/1446, merged on Aug 15 and Sep 13, respectively:

• https://github.com/monero-project/monero-gui/pull/1511
• https://github.com/monero-project/monero-gui/pull/1523
• https://github.com/monero-project/monero-gui/pull/1447
• https://github.com/monero-project/monero-gui/pull/1516
• https://github.com/monero-project/monero-gui/pull/1543
• https://github.com/monero-project/monero-gui/pull/1544
• https://github.com/monero-project/monero-gui/pull/1546
• https://github.com/monero-project/monero-gui/pull/1547
• https://github.com/monero-project/monero-gui/pull/1494
• https://github.com/monero-project/monero-gui/pull/1542
• https://github.com/monero-project/monero-gui/pull/1553
• https://github.com/monero-project/monero-gui/pull/1446

Notes:

• Support for creating hardware wallets in https://github.com/monero-project/monero-gui/pull/1446 is disabled since there's currently no hardware wallets for Aeon.
• All the translation files are left untouched. Anyone is welcome to adapt them to Aeon.