fixed rendering bug for th, zh, ja

[daksh-sehgal]

Fixes issue #80 by not excluding Chinese origin characters when calling SplitText(). Also fixes a rendering bug with zero width characters (found in languages like Thai).

[Kohirus]

This fix is great, but there is a problem that if the text contains Spaces, it will force line breaks.

[Kohirus]

I found the source of the problem, commented out the following in the MulitCell(), as well as the SplitText() and write(). Why do spaces need to be wrapped, maybe some languages ​​require this?

if c == ' '  {
     sep = i
     ls = l
    ns++
}

[sbinet]

thanks for the PR. (and apologies for the belated answer)

could you add a testcase to this PR ?
(perhaps also adding a testcase exercizing what @Kohirus mentioned ?)

thanks again.