readme: add neatvi ref, pike: misc style fixes

README

@@ -43,6 +43,9 @@ or class is a space we want to match not assert at. But the code for it was too
 dirty and I scrapped it. Syntax for word assertions are like posix C library, not
 the pcre "\b" which can be used both in front or back of the word, because there is
 no distinction, it makes the implementation potentially even uglier.
+* Assert flags like REG_ICASE,REG_NOTEOL,REG_NOTBOL and lookahead inside
+negated bracket are implemented here (also shows use case in real world project):
+https://github.com/kyx0r/neatvi/blob/pikevm/regex.c
 
 NOTES
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