Security: Allow toString() be (in general) "ticker (name)"

[pfalcon]

For many people, ticker is more familiar than security name/title (this
is especially true for funds). toString() is used e.g. in dropdown boxes
for security selection. So, if a corresponding preference is enabled by
user, include ticker in the display string.

If ticker symbol is not available, or matches the security name, toString()
will return just "name", as before.

[pfalcon]

This is updated version of #4183, based on (ongoing) discussion in #4182 . A checkbox preference Prefer 'symbol' to identify securities is added, by default the behavior is the same as before, but if the pref is checked, SYMBOL (name) will be used.

[pfalcon]

Example of security selection dropdown before the setting activation:

The setting activated:

Example of security selection dropdown after the activation:

[pfalcon]

@buchen : What do you think about this solution?

[buchen]

What do you think about this solution?

I am just looking at it.

I'll push an alternative implementation that
a) stores the property in the file (in order to re-use it across installation and on the mobile app)
b) allows to pick other identifier as well (because ticker is a special case)

I am not done yet. For example the sorting is not correct yet (see also your screenshot above).
And the label and translations are missing.

But as I will break for lunch soon, I will push a draft pull request and would appreciate if you can test it.

[pfalcon]

@buchen :

But as I will break for lunch soon, I will push a draft pull request and would appreciate if you can test it.

Thanks! Commented at #4265 (comment)

[buchen]

Superseeded by #4265