Deprecate most "Event::every*" methods

[PabloKowalczyk]

Q	A
Fixed tickets	no

As discussed in #307 most Task::every*() methods are not really "every". Take everyFourtyMinutes for example, expected run dates are: 00:00, 00:40, 01:20, 02:00, but actual dates are: 00:00, 00:40, 01:00, 01:40, so task doesn't run every fourty minutes (same rules applies to "hour", "day" and "moth" calls). To reduce ambigious behavior i decided to deprecate most Task::every*() methods and add/leave only real "every" methods like everyTenMinutes or everyThirtyMinutes.
With this change IDE can autocomplete "new" methods, which is not a case earlier.
Migration path is not complex, use one of "new" methods or provide Cron expression by Task::cron method.
"New" methods:

• everyMinute
• everyTwoMinutes
• everyThreeMinutes
• everyFourMinutes
• everyFiveMinutes
• everyTenMinutes
• everyFifteenMinutes
• everyThirtyMinutes
• everyTwoHours
• everyThreeHours
• everyFourHours
• everySixHours