Do not allow upgrading when entity is producing and vice versa.

Before this patch, when entity was upgrading and producing and finished upgrading before production, production was canceled. That meant player assumed unit/tech will be ready in certain time but it will not. Also fixing interference between upgrade and production animations.

Differential Revision: D2652
Reviewed by: bb
Comments by: Stan, Freagarach
Fixes: #5749
Refs: #2706