(svn r2297) - CodeChange: server-check the next batch of commands.
- CodeChange: since only the server will be able to modify difficulty settings, leave the checking of correct values besides, and trust users will join legit servers.
- CodeChange: for renaming signs, only check if GetDParam(); eg _decode_parameters is empty ('\0') or not, instead of the extra check of players, etc. That basically does the same thing. Also dirty sign two times when renaming, once before, once after the action. Because if the name becomes shorter and you update only after, garbage remains on the screen.
- CodeChange: made GetMaskOfTownActions() available to the town-cmd to double-check if the action was available to the player. For this purpose the hardcoded _local_player has been removed from the function and is now passed as a parameter.

(svn r2296) - Fix (regression): oops, forgot the MS code-decleration rules :p

(svn r2295) - Fix: you were still able to delete any tile if you were not careful with CmdDestroyCompanyHQ. Fixed this; thanks HackyKid.

(svn r2294) - CodeChange: check the service interval settings when changing of all vehicle-types. To simplify things introduce GetServiceIntervalClamped() that returns the same or clamped value of the new service interval. There were some inconsistencies in the gui files so I had to change those, and const correctness kicked in, so it's a bit messy at certain points.

(svn r2293) - Fix (regression): You couldn't modify commands anymore; fixed. (|| and && are kinda confusing with !=) :P

(svn r2292) - Fix (regression): make error message more general for console errors. Dedicated servers are properly filtered out when requesting player-password.

(svn r2291) - Fix (regression): When a client joined it changed the server-player's name. Funny effect; but not desired. Thanks for pointing it out Tron. It needed a bit of hacking, but is not less of a hack than the one used before :)

(svn r2290) - CodeChange: protect the next batch of commands. This brings us to a total of 61, which is 53% :)
- CodeChange: To correctly accept engine-prototypes, the best-player checking has been moved to its own function, I hope it functions the same as before.
- CodeChange: Added symbolic types of PlayerID, OrderID and EngineID. For engines also added GetEngine() and IsEngineIndex(), similar to the other such functions.
- CodeChange: To correctly build industries, some tables have been moved to build_industry.h. The only way to find out currently if an industry is valid in a climate is by looping all industries and checking if it matches. Also to comply with the patch setting build_rawmaterial_industries, it is assumed that these industries do not accept any cargo of any type. This can and probably should changed in the future to some flag in their struct. Also use _opt_ptr instead of _opt.
- CodeChange: implemented the HQ checking code inspired by MarkR2 in "[ 1190944 ] Many commands not checked for security". Unfortunately it is impossible to prevent only deleting a HQ by a modified client atm.
- CodeChange: For insert order and modify order their parameters are implicitely truncated to 8 bits, instead of the 16 bits said in the comments.

(svn r2289) - Fix (regression): check p1 param of road-depot building instead of unused p2 (typo). Thanks peter1138.

(svn r2288) - CodeChange: protected the next batch of commands (41 so far, out of 115).
- CodeChange: changed the airport gui airport-type checking. Added function GetValidAirports() that returns bitmasked availibility, is also used for checking.
- CodeChange: to check tree-planting, 2 const arrays have been moved to table/tree_land.h (type and count)
- CodeChange: added IsTownIndex() in following of IsStationIndex(), etc.
- Fix (regression): road tunnels did not work anymore, forgot that their type was 0x200 (documented now)