Improve / Add more coursework required features

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• Ranges

• Lists

• Steps

• Use of Names in (Month & Day of Week Fields)

• Allow for Ranges, Lists & Steps to Co-exist in the same fields

• Special Strings

• Make sure the above checklists are all working 100%

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Please check on the repository for the new updated crontab-ui file with changes. Some stuff maybe completed, but not thoroughly checked to be 100% working.

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As required by the coursework specification:

• Highlighted in orange/red box stuff to be done/are almost done:

[migbash]

Nearly there, more validation required to check all is working & update the documentation & README files

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Coursework ready for submission