refactor: make metric diameter primary

data/help/texts.json

@@ -316,7 +316,7 @@
       "Q: Why can't I carry anything?\nA: At the start of the game you only have the space in your pockets.  A good first goal of many survivors is to find a backpack or pouch to store things in.",
       "Q: Help!  I started a fire and now my house is burning down!\nA: Fires will spread to nearby flammable tiles if they are able.  Lighting a fire in a set-up brazier, stove, wood stove, stone fireplace, pit, or even in a kitchen stove will stop it from spreading.  Fire extinguishers can put out fires that get out of control.  You can put out a fire in the fireplace by examining it.",
       "Q: I'm cold and can't sleep at night!\nA: Gather some clothes and put them in the place you use to sleep in.  Being hungry, thirsty, wet, or injured can also make you feel the cold more, so try to avoid these effects before you go to sleep.  Pillows and some other appliances will help you sleep, and the quality of your sleeping spot is also very important.",
-      "Q: There are too many calibers and guns.  It confuses me - I don't usually understand what is compatible with what.\nA: Try to remember few usual calibers: \n9x19 (or simply 9mm) - fits most basic pistols (Glock, for example) and SMGs, quite easy to find and gets job done versus usual zombies;\n 00 buckshot - for most shotguns.  Very powerful against unarmored target at closer ranges;\n .223 (5.56) - for rifles.  Good long range option.\n .308 (7.62) - for even more powerful rifles.  Also good long range option.\n  It should be enough in the beginning.  Or even just grab any shotgun, fill it with buckshot and give them hell!",
+      "Q: There are too many calibers and guns.  It confuses me - I don't usually understand what is compatible with what.\nA: Try to remember few usual calibers: \n9x19mm (or simply 9mm) - fits most basic pistols (Glock, for example) and SMGs, quite easy to find and gets job done versus usual zombies;\n 00 buckshot - for most shotguns.  Very powerful against unarmored target at closer ranges;\n 5.56mm (.223) - for rifles.  Good long range option.\n 7.62mm (.308) - for even more powerful rifles.  Also good long range option.\n  It should be enough in the beginning.  Or even just grab any shotgun, fill it with buckshot and give them hell!",
       "Q: I have a question that's not addressed here. How can I get an answer?\nA: Check the wiki, or ask the helpful people on the forum or at the chat channels. Links are provided in MOTD in the main menu."
     ]
   }