Javadoc of SpreadsheetView does not show images with picker examples

[bykka]

Javadoc of SpreadsheetView
https://controlsfx.bitbucket.io/org/controlsfx/control/spreadsheet/SpreadsheetView.html
has part Pickers with broken urls to images

Urls are:
https://controlsfx.bitbucket.io/org/controlsfx/control/spreadsheet/pickerExample.png
https://controlsfx.bitbucket.io/org/controlsfx/control/spreadsheet/pickerExample2.png

but should be
https://controlsfx.bitbucket.io/org/controlsfx/control/spreadsheet/pickerExample.PNG
https://controlsfx.bitbucket.io/org/controlsfx/control/spreadsheet/pickerExample2.PNG

Or images should be renamed and use lowercase file extentions