Add configuration for mails

I do nearly all my mails with neomutt. So, I naturally edit mails with
vim (neovim to be precise). These settings add a couple of autocompletes
for very common mail-phrases. Furthermore I restrict the line-length of
my mails to 78 chars per line, since this is the recommended line-length
according to RFC-5322.

Reference: https://datatracker.ietf.org/doc/html/rfc5322#section-2.1.1

.config/nvim/lua/config/defaults.lua

@@ -132,6 +132,16 @@ vim.api.nvim_create_autocmd("FileType", {
 		vim.opt_local.colorcolumn = "72"
 	end,
 })
+-- mail
+vim.api.nvim_create_autocmd("FileType", {
+	pattern = "mail",
+	group = configgroup,
+	callback = function()
+		-- https://datatracker.ietf.org/doc/html/rfc5322#section-2.1.1
+		vim.opt_local.textwidth = 78
+		vim.opt_local.colorcolumn = "78"
+	end,
+})
 -- lua
 vim.api.nvim_create_autocmd("FileType", {
 	pattern = "lua",

.config/nvim/snippets/mail.snippets

@@ -0,0 +1,37 @@
+snippet dearall English greeting
+	Dear Sir or Madam,
+  
+	${0}
+
+snippet dearmam English greeting females
+	Dear Ms. ${1},
+  
+	${0}
+
+snippet dearsir English greeting males
+	Dear Mr. ${1},
+  
+	${0}
+
+snippet kindly English mail closing
+	Kind regards
+	${0}
+
+snippet sehrfrau German greeting females
+	Sehr geehrte Frau ${1},
+  
+	${0}
+
+snippet sehrherr German greeting males
+	Sehr geehrter Herr ${1},
+  
+	${0}
+
+snippet sehralle German greeting
+	Sehr geehrte Damen und Herren,
+  
+	${0}
+
+snippet mfg German mail closing
+	Mit freundlichen Grüßen
+	${0}