More events from Suunto DM4 added

I got a few more events from a new sample database. Bookmark heading is
now shown if such information is stored. Also the unknown events display
the event number for easier identification.

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Fix import when locale set to decimal comma

This should take care of locale caused problems when the input uses decimal
point but locale uses decimal comma. Also the sample I have of Suunto DM3
format weight is represented with comma instead of dot so converting that as
well.

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
Test if .bak file is supported database dive log

Even though the documentation states to rename DM4 backup to .db file
extension, accept the default .bak extension as well. This, however,
does not enable the .bak extension in file selection dialog (so .bak
files must be given as command line parameters).

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
DM4 import pressure detection fix

Seems that the database can contain either null or empty string when
there is no pressure data available. Changing the pressureblob
validation to reflect this new information.

Since the temperature profile is binary data, we most likely should
accept 0 as a valid value. My samples have null in this blob if there is
no data so it seems to be different than the pressure blob. But of
course there are no guarantees...

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
DM4 import user documentation update

Instructions how to find the effective database file from DM4, using
this method there is no need to rename the backup as the original file
works as is when found from a random directory structure.

Signed-off-by: Miika Turkia <miika.turkia@gmail.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>