Do not highlight the line on the other side when hiding added/deleted imports

[anchouls]

[tsantalis]

Anna Potriasaeva (@anchouls) Zarina Kurbatova (@onewhl)

You can further improve the import changes visualization by using the following APIs:
UMLImportListDiff.getCommonImports()
UMLImportListDiff.getGroupedImports()
UMLImportListDiff.getUnGroupedImports()

The screenshot below shows an example of import grouping, where 10 import declarations were replaced with a single on-demand .* import declaration