theo-cli: fix syntax

.gitignore: add .vscode to ignored files

theo-cli: document SSH options

theo-agent: document support to multiple public keys for signatures

theo-agent: document -use-dns

Document -with-password-authentication flag

Merge pull request #6 from gizero/theo-cli-accounts-fix-syntax-and-indentation

theo-cli: usage: accounts mod: fix indentation

theo-cli: usage: accounts add: fix alien Markdown syntax

Conf: remove release code

Theo-agent: improve formatting

Theo-agent: add new arguments

Theo-agent: signed keys: you can set verify: True also in the configuration file

Theo-cli: signed keys: update command to generate private key

Rephrase OpenSSH < 6.9 limitation