Rework logging

[iorlas]

Damn, we need improved logging:

1. Log levels
2. Log levels control from INI config
3. VA_ARGS parsing
4. Table-oriented struct. Separate main parts using \t.
5. Support multiple types of backend: OutputDebug, Textfile.

[iorlas]

Add chained logging:

log("Operation")
log("complete")
=> "Operation: complete"

If last log-string wasnt a "Operation"(needed first part of chain), repeat it. So, we need to show a time-delta.