Since more and more information in now available through the CPU
registers, those require DLV_HOST access to be a bit better handled
than it is...

- in backtraces, (void) functions should be listed with '()' as arguments instead of ''
- factorized code for diplaying information about a local/parameter
- fixed a couple of bugs here
- rewrote format specifiers for print commands (do no waste space for padding data)
- added support for new wine's dbghelp extension for local/parameter
  variables being out of scope

They are stored internally as offsets to the start of the function
which embeds the block.