Request new feature. - #1553

When changing an indexed column from a table using the Edit Table dialog
we try to update the corresponding indices as well. So if a column is
renamed all references to it in the indices are renamed accordingly.
This, however, didn't take into account that you can also remove
columns. While trying to update the column to nothing, the application
would crash. This is fixed by this commit. It doesn't crash anymore and
now removes the column from the index as expected.

See issue #1115.

Editing a table column in the Edit Table dialog accidentally committed
all prior changes to the database, effectively clicking the 'Write
Changes' button while working on the table. This is no problem if your
working on a clean database, but is a problem if you have made other
changes before. In the latter case you lose the ability to roll them
back and you can't use the Cancel button in the Edit Table dialog
anymore.

See issue #1116.

See issue #1111.

See issue #1111.

This fixes a regression introduced in d1e3e98 which makes it
impossible to open encrypted databases with single quote characters in
their passphrase.

See issue #1105.

Change the tab order in the encryption dialog so that the password
editor is the widget that is selected by default. That makes it possible
to type in the passphrase right away without navigating to the widget
first.

See issue #1095.

See issue #1097.

See issue #1095.

See issue #1113.

Don't highlight all the horizonzal headers when selecting a certificate
row in the preferences dialog.

See issue #1087.

As per suggestion by @chrisjlocke, this commit removes the trailing
'.00' bit for round numbers.

As pointed out by @Vort in #1107

If there is a local clone of a remote database but the remote database
has been updated to a newer version in the meantime, we're now asking
the user what to do. The choice is between downloading the newer version
and overwriting the local one with all the changes it might have
contained or opening the local version and not downloading anything.

See issue #1096.

The JSON format generated by the server has changed.

Extend the filter syntax to allow filtering for fields that are not
equal to NULL.

See issue #1124.

Instead of disabling the entire edit dock when the database is opened in
read only mode, only disable all buttons for making changes to the
field. This way the data can still be read using the edit dock.

See issue #1123.

At the moment when user types a custom type into the type combo box and
doesn't press enter, the entered type isn't used. This patch tries to fix
the problem by installing an event filter for the combo box and checking
when it loses focus - when it does, it performs type updates too.

On the way the patch also changes the signal used inside moveCurrentField()
from activated() to currentIndexChanged() to make it consistent with the
rest of the file.