filters not unicode safe

[oberhamsi]

• strings.capfirst, strings.lower, strings.upper - These do not take care of locale-sensitive character capitalization rules for Turkish, Serbian, Croatian, etc.
• strings.truncatechars - This is not sensitive to Unicode surrogate characters or combining characters, and therefore may truncate in the middle of a character. This is particularly troublesome in writing systems that rely heavily on combining characters such as Thai or most of the Indic writing systems like Devanagari, Kannada, Tamil, etc.

[ehoogerbeets]

Missed a line in the first point:

• strings.capfirst, strings.lower, strings.upper - These do not take care of locale-sensitive character capitalization rules for Turkish, Serbian, Croatian, etc.

All 4 of these can be handled properly by ilib. Eventually, I will create an ilib-filters ringo package that will have plugin filters for these things based on ilib.