cron type patterns don't fully support cron syntax

[vchepkov]

cron module doesn't allow the following pattern, which is a valid syntax

hour => '1-23/2'

[scorillo]

I can confirm

#66 fixed the problem only for */n where n < 3
same fix should be made for interval/n where n < 3

( \/ ( 1?[0-9]|2[0-3]|[3-9] ) )? versus ( \/ ( 1[0-9]|2[0-3]|[3-9] ) )? ?

[scorillo]

@bastelfreak ^^^

[bastelfreak]

hey people. I current'y don't have time to develop and test a fix for this. can one of you raise a PR with a test that fails or also the code to make it work?

[scorillo]

@bastelfreak #94 - test that will fail with the current code