Fixed accidental warning for $".."
Generalized for f in $(ls) warning, due to many edge cases.
Added $PWD as a variable likely to contain spaces
Don't warn about IFS= read ..
Don't warn for $ on $(( ${array[refs]} ))
Don't warn for \. (regex) and \, (printf "%q" output)
Don't warn about echo "--------" is posix mode
Tried to make [ foo=bar ] messages simpler
Fixed parsing of IFS= read as single assignment
Warn about suspicious quotes in "foo "$var" bar"
Fixed up some warning messages.
Allow lack of spaces/separators in for((;;))do ..
Don't warn about redirecting sudo to /dev/null
Clarified warning for expr