Resolve "Add additional information in overlay dialog"

See merge request !1038

Resolve "Data overlay - colouring by column identifier_xxx does not work"

See merge request !1037

Resolve "this exception is not handled properly (on project remove)"

See merge request !1035

Resolve "if map has SHOW OVERVIEW, the legend/comment/clear are not displayed at all"

See merge request !1034

when there is no background don't check if overlay is nested

See merge request !1032

if by any chance user is null then reload webpage (but it should never happen)

See merge request !1025

Font colour of text area was preserved in Empty view

See merge request !1024

arrows handling in SBML fixed

See merge request !1023

content with type of data overlay could crash upload

See merge request !1022

uploading of the page with low internet connection speed produced empty screen for several seconds/minutes