Json output

pour généraliser les sorties json sur toutes les commandes

requested review from @Nicolas80

assigned to @pokapow

basé sur la branche choose-ed25519

Really nice to support JSON output for all of those (as long as we don't put the JSON format by default )

approved this merge request

mentioned in issue #47

added 12 commits

• 8760c3bd...3738e8b7 - 2 earlier commits
• 44073020 - * Adding `-c` crypto scheme parameter (with default ed25519) in different places
• da7c790d - * Added some logic between arguments of `vault import`; can't provide both...
• 8bf81cbc - * Adapted catch_known of predefined derivations to properly handle both...
• 0da71079 - * reverted most of the commit e9cd6a99: "Add secret format in database and display"
• bbd95707 - Added extra message when the DB parsing of DbAccountId fails, so we know for...
• f9beaf54 - * Updated version to 0.4.1
• 2843da7b - use json output for all usefull commands
• c4f8f3dd - Fixes after rebase of modified upstream branch
• f72566bd - * changes from `cargo fmt`
• a6bc5180 - * small fix for `vault use` with Json output format.

Compare with previous version

added 5 commits

• bb54cc00 - 1 commit from branch master
• e4b8f061 - use json output for all usefull commands
• a094482d - changes from `cargo fmt`
• 63eed5bd - * small fix for `vault use` with Json output format.
• 503d4caa - Adapting `vault inspect`

Compare with previous version