Bug? Whitespace trimming
my command:

```
text="`cat subset.txt`" && node_modules/.bin/fontmin -t "$text" fonts/lato/lato__latofonts_com.ttf > fonts/lato/lato__fontmin.ttf
```

in subset.txt:

```
! "#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[]^_`abcdefghijklmnopqrstuvwxyz{|}~©«»ЁАБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯабвгдежзийклмнопрстуфхцчшщъыьэюяё‐‑‒–—―‘‚“„…‰™
```

whitespace character is in the set
but when I open the .ttf in FontForge, I see that the space character in the font is missing.
空白字符是集合
但是当我在FontForge打开.TTF，我看到，在字体的空格字符缺失。
