Add UpdateFlags injection

[naeem76]

PR for #101

I have just started looking into Cities modding, so apologies if there's any issue, I'm planning to contribute more if things go well.

Tested with 2 local instances of cities, and abandoned buildings were synced.

[kaenganxt]

Hi, thank you for your contribution and sorry for taking so long to respond.
Your code looks good to me!
The build is failing because it looks like you forgot to add the changes of your CSM.csproj
Please add them to this PR.
I'll also test it out tomorrow.

[naeem76]

No probs on the time, I did some more testing afterwards, and in extreme scenarios it is a bit desynced, because server and client are doing their own thing, probably need to cancel any client side actions for these. I tried using harmony to skip original method when client side, but not working great. I'll check later when i have more time!