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In preparation of adding Arabic math symbols (outside BMP).
Start adding Arabic math symbols

A quick job, I’m not happy about the design of almost all the glyphs:
* In a math book I have (printed in Bulaq Press), the isolated math
  symbol have different design from the regular isolated glyphs, which
  makes them quite distinct. Ditto for initial symbols.
* The tailed symbols are really ugly, but I need to draw proper isolated
  symbols first, to base on them.
* No looped symbols yet, I have just regular isolated symbols as place
  holders.