tools: support `v missdoc .` instead of `v run cmd/tools/missdoc.v .`

cmd/tools/vmissdoc.v

@@ -5,8 +5,8 @@ import os
 import flag
 
 const (
-	tool_name        = os.file_name(os.executable())
-	tool_version     = '0.0.3'
+	tool_name        = 'v missdoc'
+	tool_version     = '0.0.4'
 	tool_description = 'Prints all V functions in .v files under PATH/, that do not yet have documentation comments.'
 	work_dir_prefix  = normalise_path(os.real_path(os.wd_at_startup) + '/')
 )

cmd/v/help/missdoc.txt

@@ -0,0 +1,16 @@
+v missdoc 0.0.4
+-----------------------------------------------
+Usage: v missdoc [options] PATH [PATH]...
+
+Description: Prints all V functions in .v files under PATH/, that do not yet have documentation comments.
+
+Options:
+  -h, --help                Show this help text.
+  -t, --tags                Also print function tags if any is found.
+  -d, --deprecated          Include deprecated functions in output.
+  -p, --private             Include private functions in output.
+  --js                      Include JavaScript functions in output.
+  -n, --no-line-numbers     Exclude line numbers in output.
+  -e, --exclude <multiple strings>
+                            
+  -r, --relative-paths      Use relative paths in output.

cmd/v/v.v

@@ -28,6 +28,7 @@ const (
 		'doctor',
 		'fmt',
 		'gret',
+		'missdoc',
 		'repl',
 		'self',
 		'setup-freetype',