Fix bugs and make improvements

- Fix regression with `%lu`
- Added some more headers witnessed in the wild
- Added `-M INT` option to redbean to tune max payload size
- Work around InfoZIP 256 character limit on comment line size

tool/net/demo/redbean.lua

@@ -274,23 +274,23 @@ local function main()
    Write('<dl>\r\n')
    Write('<dt>m\r\n')
    Write('<dd>')
-   Write(tostring(m))
+   Write(string.format("%q", m))
    Write('\r\n')
    Write('<dt>a\r\n')
    Write('<dd>')
-   Write(tostring(a))
+   Write(string.format("%q", a))
    Write('\r\n')
    Write('<dt>b\r\n')
    Write('<dd>')
-   Write(tostring(b))
+   Write(string.format("%q", b))
    Write('\r\n')
    Write('<dt>c\r\n')
    Write('<dd>')
-   Write(tostring(c))
+   Write(string.format("%q", c))
    Write('\r\n')
    Write('<dt>d\r\n')
    Write('<dd>')
-   Write(tostring(d))
+   Write(string.format("%q", d))
    Write('\r\n')
    Write('</dl>\r\n')