Set default log level to Info, we don't use debug anyway and it just fills the logs with other crates info.

- Added quoted_printable crate to encode the e-mail messages.
- Change the way the e-mail gets build to use custom part headers.

Reorganized the icons code a bit.

Return 404 instead of 400 when no accounts breached.

Trim spaces from admin token during authentication and validate that the admin panel token is not empty

Added newlines to config options to keep them a reasonable length.

Print a warning when an env variable is being overriden by the config file, and reorganize the main file a bit.
Modified the JWT key generation, now it should also show the output of OpenSSL in the logs.

Removed list of mounted routes at startup by default, with option to add it back. This would get annoying when starting the server frequently, because it printed ~130 lines of mostly useless info

Squashed commit:

[ece2260] Plaintext send_org_invite

[01d4884] Plaintext pw_hint_some

[6ce5173] Plaintext pw_hint_none

[881af3e] Plaintext invite_confirmed

[ce78621] Plaintext invite_accepted

[13a44a4] Rename send_org_invite.hbs to send_org_invite.html.hbs

[b52bf2f] Rename pw_hint_some.hbs to pw_hint_some.html.hbs

[e0d1aeb] Rename pw_hint_none.hbs to pw_hint_none.html.hbs

[898dbcd] Rename invite_confirmed.hbs to invite_confirmed.html.hbs

[107af31] Rename invite_accepted.hbs to invite_accepted.html.hbs

[d26d662] Updated send_org_invite template

[71f47af] Updated pw_hint_some template

[c2ca3c2] Updated pw_hint_none template

[50f8bfb] Updated invite_accepted template

[17f96f8] Updated invite_confirmed template