vlib: add toml module + tests (#11964)

examples/toml.v

@@ -0,0 +1,48 @@
+import toml
+
+// Complete text from the example in the README.md:
+// https://github.com/toml-lang/toml/blob/3b11f6921da7b6f5db37af039aa021fee450c091/README.md#Example
+const toml_text = '# This is a TOML document.
+
+title = "TOML Example"
+
+[owner]
+name = "Tom Preston-Werner"
+dob = 1979-05-27T07:32:00-08:00 # First class dates
+
+[database]
+server = "192.168.1.1"
+ports = [ 8000, 8001, 8002 ]
+connection_max = 5000
+enabled = true
+
+[servers]
+
+  # Indentation (tabs and/or spaces) is allowed but not required
+  [servers.alpha]
+  ip = "10.0.0.1"
+  dc = "eqdc10"
+
+  [servers.beta]
+  ip = "10.0.0.2"
+  dc = "eqdc10"
+
+[clients]
+data = [ ["gamma", "delta"], [1, 2] ]
+
+# Line breaks are OK when inside arrays
+hosts = [
+  "alpha",
+  "omega"
+]'
+
+fn main() {
+	doc := toml.parse(toml_text) or { panic(err) }
+	title := doc.value('title').string()
+	println('title: "$title"')
+	ip := doc.value('servers.alpha.ip').string()
+	println('Server IP: "$ip"')
+
+	toml_json := doc.to_json()
+	println(toml_json)
+}