Add prototype for adding notes

How can I keep the database and the in-memory list in sync?
Simplify the creation of a test db.
Simplify bulk insert for testing
Add todo suggesting to use QTableModel
Add links to Qt CSS examples
Convert inserted rows to html
Clear the input widget after inserting comment
Don't allow rich text to be inserted

Only markdown is allowed. We probably have to figure out a way to convert
pasted images into markdown links.
highlight current line in editor

Just experimenting.
Wrap html text properly
MarkdownEditor: reserve enter key for submit
strip QtCore prefix when importing
Strip QtGui prefix when importing
MarkdownEditor: add editFinished() signal
Add dropEvent(..)
Remove outdated todo comments
Fetch notes from db in reverse order of insertion
Use constant for insert sql stmt
Use constant for update sql stmt
Sync only updated entries from db