As encoded-data might be large and not really useful to be displayed in
the UI of MISP. We moved it to an `attachment` attribute type.
We keep the `attachment` as Base64 to avoid any risk of people
downloading or executing as potential malicious file. So it MUST be
encoded in Base64 as it was before.
- Fixed some matching type instead of text (like size-in-bytes or integer)
- Added many fields and replace name with `_` to `-`
- Added some basic description