BUL - Flag with the correct Bulgarian CoA

[lehmannmo]

Currently, Bulgaria's flag has the coat of arms on it which was used between 1881 and 1927. I propose to change the CoA to the one that was historically used in the 1930s:

It also makes the flag look a bit better as the current CoA is way too small (especially in comparison to flags like the Serbian one, which is quite similar in the overall appearance but sports a CoA twice or trice the size of the Bulgarian one).

[Augenis]

This will be considered internally.