NoteMetadata - Create class to handle all note metadata

[selimrbd]

NoteMetadata's attributes:

• Frontmatter
• InlineMetadata
• BodyTags

Note calls this class to handle everything metadata

functionalities:

• [x] add(k,v,where)
• [x] remove(k,v,where)
• [x] .move(k, where): move a metadata from 1 place to another (ex: frontmatter -> inline)
• [x] remove_duplicate_keys(keep_in: MetaType):
• [x] remove_duplicate_values(where: MetaType):
• [x] update_content(order: Optional[OrderType]): update the content of the parent note

update_content(order: OrderType, order_frontmatter: bool, order_inline: bool)

[selimrbd]

Done