Mostly cmpsc debug updates

CMPSC logic changes
- Maintain alphabetic order in function variables (sorry!)
- Use memset() instead of raising all individual bits at permanent dead end

CMPSC debug changes, only active with OPTION_CMPSC_DEBUG defined
- Added variables to expansion context for statistics
- Deleted unused parameter "is" in cmpsc_print_ece()
- Generate debug msgs on empty in- or output
- Generate debug msg on permanent dead en discovery
- Maintain and report expand statistics: index symbols; alphabet characters; cache hits; bytes in; and bytes out, including percentages
- Report correct ece index, it reported the newly fetched one
- Use same format in fetch_iss as in store_iss by showing all index symbols