added helper "action.d/helpers-common.conf", and `_grep_logs` part-command for actions needed grep logs from multiple log-files
test cases: executing of some complex actions covered
- starting service in normal mode (without forking)
- does not restart if service exited normally (exit-code 0, e.g. stopped via fail2ban-client)
- does not restart if service can not start (exit-code 255, e.g. wrong configuration, etc.)
- service can be additionally started/stopped with commands (fail2ban-client, fail2ban-server)
- normalize calling parameters (persistent parameters moved from function arguments to filter member variables)
- save last line as lambda instead of return it as string (lazy convert of process line tuple to string on demand, needed in fail2ban-regex only)
- datedetector rewritten more strict as earlier;
- default templates can be specified exacter using prefix/suffix syntax (via `datepattern`);
- more as one date pattern can be specified using option `datepattern` now (new-line separated);
- some default options like `datepattern` can be specified directly in section `[Definition]`, that avoids contrary usage of unnecessarily `[Init]` section, because of performance (each extra section costs time);
- option `datepattern` can be specified in jail also (jails without filters);
- if first group specified, only this will be cut out from search log-line (e. g.: `^date:[({DATE})]` will cut out only datetime match pattern, and leaves `date:[] failure ip...` for searching in filter);
- faster match and fewer searching of appropriate templates (DateDetector.matchTime calls rarer DateTemplate.matchDate now);
- standard filters extended with exact prefixed or anchored date templates;
template cache introduced (in opposition to default template cache, holds custom templates cached by pattern for possible common usage of same template/regex);
- `datepattern = {^LN-BEG}` - only line-begin anchored default patterns
(matches date only at begin of line, or with max distance up to 2 non-alphanumeric characters from line-begin);
- `datepattern = {*WD-BEG}` - only word-begin anchored default patterns;
- `datepattern = ^prefix{DATE}suffix` - exact specified default patterns (using prefix and suffix);
common filter configs gets a more precise, line-begin anchored (datepattern = {^LN-BEG}) resp. custom anchoring default date-patterns;
thereby follow rule "shortest distance to datetime should win", so possible collision causes search though all templates;
speedup it a little bit (not possible collision if distance <= 1 or if line-begin anchoring, so break search if such template found)
By change of the distance (e.g. another format found), the pattern with smallest distance will be always preferred now.
To speedup (template lookup) resp. minimize of list reorder counts, the distance will be used as divider factor of the template weight by the templates comparison.
roedie