Map PUA bullets to Unicode in Word (#6778)
* Adding Private Unicode Area to Unicode map for Bullet character
Adding few bullet types that word uses.
* Clean up PR by @nvda-india:
* Remove U+F0B7 PUA symbol from symbol dictionary.
* Reorder and clean up the mapPUAToUnicode dict.
* More consistent code style in _normalizeFormatField().
* Update U+F0E8 to use the same mapping as Word uses when saving to plain text.
* Update U+F0FC based on http://www.alanwood.net/demos/wingdings.html.
* Update description for U+21E8 to more closely match the Unicode name.
* Add U+F0A7, used for bullets on level 3,
based on https://en.wikipedia.org/wiki/Symbol_(typeface)#Encoding.
* Review actions.
