Rename the hasErrors() method and containsErrors property

[RomanTsukanov]

Method names usually start with a verb. We should rename the hasErrors() method to validate().

We have many properties that start with "has": hasDescription, hasTitle, hasOther, etc. The containsErrors property works similarly but named differerntly. We should rename this property to hasErrors.

[andrewtelnov]

@RomanTsukanov containsErrors cannot be renamed to hasErrors because there's already the hasErrors method. There are also hasCurrentPageErrors() and hasPageErrors() methods. We need other names.

Thank you, Andrew

[RomanTsukanov]

@andrewtelnov Okay, we have no choice but to leave containsErrors as is then. Other renamings are as follows: hasErrors() -> validate() hasPageErrors(page) -> validatePage(page) hasCurrentPageErrors - remove, use validatePage(survey.currentPage) instead

[metaturso]

Would you mind throwing a rename of isCurrentPageHasErrors into this mix? This makes no grammatical sense and could easily be called hasErrorsOnCurrentPage or something like that (not to be confused with the hasCurrentPageErrors being deprecated here.)