vlib: transfer intro to readme; normalize comments

vlib/flag/flag.v

@@ -1,49 +1,5 @@
 module flag
 
-// module flag for command-line flag parsing
-//
-// - parsing flags like '--flag' or '--stuff=things' or '--things stuff'
-// - handles bool, int, float and string args
-// - is able to print usage
-// - handled unknown arguments as error
-//
-// Usage example:
-//
-//  ```v
-//  module main
-//
-//  import os
-//  import flag
-//
-//  fn main() {
-//  	mut fp := flag.new_flag_parser(os.args)
-//  	fp.application('flag_example_tool')
-//  	fp.version('v0.0.0')
-//  	fp.description('This tool is only designed to show how the flag lib is working')
-//
-//  	fp.skip_executable()
-//
-//  	an_int := fp.int('an_int', 0, 0o666, 'some int to define 0o666 is default')
-//  	a_bool := fp.bool('a_bool', 0, false, 'some \'real\' flag')
-//  	a_float := fp.float('a_float', 0, 1.0, 'also floats')
-//  	a_string := fp.string('a_string', `a`, 'no text', 'finally, some text with "a" an abbreviation')
-//
-//  	additional_args := fp.finalize() or {
-//  		eprintln(err)
-//  		println(fp.usage())
-//  		return
-//  	}
-//
-//  	println('
-//  		  an_int: $an_int
-//  		  a_bool: $a_bool
-//  		 a_float: $a_float
-//  		a_string: \'$a_string\'
-//  	')
-//  	println(additional_args.join_lines())
-//  }
-//  ```
-
 // data object storing information about a defined flag
 pub struct Flag {
 	pub: