d84e78e [wallet] Specify wallet name in wallet loading errors (John Newbery)
a6da027 Reject invalid wallet files (João Barbosa)
3ef77a0 Reject duplicate wallet filenames (João Barbosa)
Pull request description:
This PR prevents loading the same wallet more than once in a multi wallet scenario. It also prevents loading with invalid files: non regular files or symlinks.
Tree-SHA512: 45bf814096bb788db1c76ff334e679a10686cee7d9c8cd48fe5d924031353ace271f6fb0d4af49a34246d336945515c176920a552be7b9fbe07ab8e00e5f6e5e