Create notebooks and take notes in markdown

Some features include:

• Almost WYSIWYG markdown rendering
• Searchable through GNOME search
• Highlight and strikethrough text formatting
• App themeing based on notebook color
• Trash can
• Markdown document
• Optional line numbers
• Optional auto save
• Open links with Control-Click
• Link to other notes in Folio
• Automatically create links for bare URL's and e-mail addresses