Set White log level according to Robot log level

[eeter]

~~Keyword for setting log level for White's console log. Argument level, should accept values "info", "warn" and "debug" (case insensitive).~~

Instead of a separate keyword for setting log level, White's log level is automatically set according to the current log level of Robot:

• White's Info, Warn and Error messages logged at Robot's Info level
• White's Debug messages logged at Robot's Debug level