Better handling for labels

Small chart views may be incapable to show axis labels. For example, if there are too many ticks and the font is large enough that there is not enough room. This could happen if a chart was made for some size, but then got resized smaller than expected.

Perhaps there could be an option to tell Charts to use smaller font if the labels won't fit. Maybe the same idea as in QML Text item with minimumPointSize.

Another idea could be to make it automatically reduce the amount of ticks.

Or signal out that some labels are not visible so user could try smaller font perhaps.