Fix Unicode input for PoeCharm

[Lancej]

Fixes #6634.

Description of the problem being solved:

Allow Unicode input in EditControls when running under PoeCharm. Added a DetectUnicodeSupport function that uses DrawStringWidth to detect if running under PoeCharm and if so changes the default input filter on EditControl.

I couldn't figure out how to test Unicode input in PoeCharm, even the file boxes it should already work in didn't work for me when I switched Windows languages to try it. Maybe someone that knows more about PoeCharm can test.

Steps taken to verify a working solution:

• Tested normal PoB still filters Unicode on those controls
• Tested DetectUnicodeSupport works in PoB and PoeCharm

[Wires77]

This is pretty hard for any of the core developers to test, but it's clean enough I'm fine putting it in for those who need it. Just need to make a note to remove it if we ever get around to supporting Unicode ourselves.

[CryAngel1970]

I tested the newly added function by applying it to the source code on my computer.

Korean input is working well. thank you.

[ZdDroid]

PoeCharm input text use the UTF8 codec,The ASCII encoding range is 21-122(ANSIC WIKI), anything beyond this encoding range can be regarded as UTF-8