SPMT - v0.3.1

Added:

• New Logo (thanks to @ElysiumcoreX)
• feature: Import external masternode file to cast votes with traditional (non-ledger) masternodes.
• feature: button to toggle expiring proposals in Governance Tab

Fixed:

• check status via txid instead of address (to be able to use it with external masternodes too).
• crash when removing masternodes
• Governance Tab: keep toggle state on reload
• bug with tx_progress signal from hwdevice
• refresh voting masternodes list after entry removal
• add a check for duplicate masternode names