reduce size of data types

[simonLeary42]

768 is the maximum length that can be used as the primary key in a mariaDB table. using 769, I get this error:

#1071 - Specified key was too long; max key length is 3072 bytes 

[bryank-cs]

I think most of these fields could be reduced to 100. This would also allow for tables with multi-column indexes, if needed.

[simonLeary42]

For usernames in particular I feel like it might be worthwhile to keep more buffer, just in case we get back a really ridiculous eppn from an IDP. 255 maybe?

[simonLeary42]

groupJoinRequests, groupRequests, groupRoleAssignments, groupRoles, groupTypes are probably never going to be used

[bryank-cs]

Spec for EPPN says 128: https://www.educause.edu/fidm/attributes

[simonLeary42]

reduced to 128. Confirmed that "operator" and "requestor" are uids, which are eppns

[simonLeary42]

also reduced "operator_ip" to 15 chars, xxx.xxx.xxx.xxx

[simonLeary42]

#131

[bryank-cs]

Can merge after change for request_for

[simonLeary42]

#148