Change age bucketing values to <18 and >89

[callachennault]

For all cohorts:

• Any AGE_CURRENT over 89 will be binned to >89 and any age under 18 will be binned to <18.
• AGE_AT_SEQ_REPORTED_YEARS over 89 will be binned to >89 and any age under 18 will be binned to <18.
• For any patient such that sum(AGE_AT_SEQ_REPORTED_YEARS + OS_MONTHS) > 89, AGE_AT_SEQ_REPORTED_YEARS will be capped to >{max(0, 89 - OS_MONTHS)}.
• OS_MONTHS will be altered to have a 2 digit precision limit.