Function: curly_quotes

--Usage--
> curly_quotes(some_tagged_string)

Make quotes 'curly'.
Single and double quotation marks are changed to opening or closing versions depending on where they appear in the text.

--Parameters--
! Parameter	Type			Description
| @input@	[[type:tagged string]]	String to make quotes curly in.

--Examples--
>>> curly_quotes("He said: 'This is cool!', she said: \"No way!\" ")
>>>   ==  "He said: &#8216;This is cool!&#8217;, she said: &#8220;No way!&#8221; "
>>> curly_quotes("Also: &#8217;Wrong quotes&#8216; ")
>>>   ==  "Also: &#8216;Wrong quotes&#8217; "
