0. If parser is NULL return 0.
1. Read a line from config file. If nothing to read then return 0.
Handle continuation character. Advance lineno for each physical line.
- Discard everything past comment characher.
+ Discard everything past comment character.
2. if PARSE_TRIM is set (default), remove leading and trailing delimiters.
3. If resulting line is empty goto 1.
4. Look for first delimiter. If !PARSE_COLLAPSE or !PARSE_TRIM is set then