Enable easier execution of selected subset of validators, using ValidationExecutor
Enable easier execution of selected subsef of reporters, using ReportingExecutor
Rename the classes implementing the whole CLI application, use 'App' prefix

 * e.g. ValidatorConfig -> AppConfig
 * the new names should make it clear that the classes are actually oriented towards the whole
   application and not single Validator
readme: add how-tos - executing only specified validators and reporters
Merge pull request #10 from psiroky/executors

Enable easier execution of only specified validators and reporters; rename app classes