dialplan: extended debug message to be more useful
kamctl: support of fnmatch operator for dialplan

- do not reload rules in memory after each change in database to allow
  batch updates. Reload command has to be done explicitely
- parameters of addrule after match expression are optional
dialplan: option to allow variables in match and substitution expressions

- based on requirement from FS#429
- new parameter: match_dynamic to enable this feature
- if enabled, at load time, the values are searched for variables and if
  any found, then evaluation and pcre compilation is done at runtime
- it can work with rules that don't include variables at the same time,
  these being pre-compiled at load time
dialplan: documentation for match_dynamic parameter
kamctl: search for greadlink first

- bsd version of readlink is different than gnu version
kamdbctl: search for greadlink first

- bsd version of readlink is different than gnu version