User can manually add bookmarks on the profile display of SmartTrak.
These are stored in a table with column names which made me think of
cartesian spatial coordinates. In the end the X coordinate is the time.
This makes possible to build subsurface events in those moments of the
dive. The other interesting data is just the text entered by the user.
Suggested-by: Alessandro Volpi <volpial@gmail.com>
Signed-off-by: Salvador Cuñat <salvador.cunat@gmail.com>