Added a new "check_modes" (note trailing 's') option of type Array.
Former "check_mode" option made optional, but will override new one for BC.
Default value is [submit, blur] for BC.
Added new option value 'change' for validating fields on change - works beter with widgets like jQueryUI datepicker.
Updated docs.
Removed 'check_mode' config option completely.
Updated docs.
Throw an informative Exception on using `check_mode`
Updated docs.
Updated comment
added use statement for rxception class to make more accurate.
Merge pull request #31 from bmurashin/master

New 'change' check mode + new 'check_modes' option