Fixing various hat problems for US and USSR

M50 Reising Mags weren't resupplying properly in-battle. This update should fix this.

The new Soviet humanskins are here! The mod filesize has gone down a lot as a lot of my custom humanskins are now obsolete and no longer needed. Instead, I have used the new humanskins and assets for all the breeds that this mod adds to the game.

TL;DR - Soviet infantry have new clothes and hats!

• Finnish faction content has been REMOVED. I have made some small tweaks to the mod so that it works with Sandels' excellent Finland Overhaul mod. I have found that the two mods work well together and make for a more fun and interesting experience playing as Finland.
  
  Sandels' mod is here: https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=2875301257
  
  
• Small teaks to AI tech progression: KV, IS-series and Tiger tanks should appear a few battles earlier than before
  
• Enabled 4 out of 5 cap zones for the last few missions in each campaign
  
• Added 3xM4A2 tank squad for USSR AI
  
• Slightly buffed defender AI budget
  
• Buffed AI CP budget earlier in the campaign -- 1943 campaign AI can (rarely) deploy heavy tanks from day 1

WARNING: The last major game update broke the code I was using to remove aircraft from conquest (thanks Devs, another real winner!). You will now need to use a separate bomb-removal mod if you want to avoid AI air attacks.

Bomb removal mod:
https://gtm.steamproxy.vip/sharedfiles/filedetails/?id=3329561975

Fixing another (!!!) typo that caused crashes for some users.

Fixing a typo that stopped players from starting a new 'Very Long (1939 start)' campaign.

Research tree changes
• NEW 1940 Fallschirmjaeger squad for Germany
  
• Reduced research costs of VVS Glider Infantry squad
  
• Small changes in research costs of Sdkfz.234 variants -- with the new mid- and late-war starts you will need the 50mm Puma to deal with enemy tanks!
  Other changes
  The new AI era setting is an EXPERIMENTAL change -- it has been tested but not exhaustively. Let me know if weird stuff happens
  
• Replaced "Campaign Length" setting with a new "Campaign Length & Era" setting. Basically, you can now start a campaign with the AI using midwar and latewar units.

I've pushed this last update out as a quick fix to keep the mod working with the latest game version. This has led to some file structure changes but otherwise nothing too major.

GER players now get early Fallschirmjaegers unlocked at the start of the campaign -- this is TEMPORARY.

Fixing ammunition issues with Lewis Gun and Johnson LMG -- both weapons should now consume ammo normally and resupply normally in battle as long as they are held by their "original" owner.