Multiple whitespace before and after keywords

[benjub]

Currently, the rewrapping done by metamath.c leaves multiple whitespace characters before and after keywords, e.g., after $p in

inxpssres $p  |- ( R i^i ( A X. B ) ) C_ ( R |` A ) $=

currently in set.mm but which I'm going to fix.

Maybe the rewrap could remove multiple whitespace characters before/after $feap= and before $. and after $cvd except when the whitespace string is "LF + any number of spaces" (to allow line breaks and indented lines).