Fix nuget package (?)

Fix a silent NRE raised in some specific rare cases

Update to be compatible with GitExtensions v5.0

(that changed interface contracts)

Fix a link on Microsoft documentation that changed

v2.0.0 to be compatible with GitExtensions v4.0 (migrated to .net6)

v1.1.0 to be compatible with GitExtensions v3.4

v1.0.1: for debugging symbols

v1.0 with icon in nuget package