Added TODO for FDBIndexRow
Added TODO for TInstance.unkown/unset or something

This instance clearly just doesn't know. It sets the value to an
unset state, so it probably needs to set the type to something
similar
ValueSources.fromObject -> not-null TInstance

Also TODOs for places that might be calling fromObject with null
A couple comments regarding null tinstance
More todos
typeClassForJDBCType never returns null
more comments and todos, um, I might be confused
Created some overloads to reduce null TInstances
A whole bunch more TInstance commentary/TODO
Merge branch 'master' into fix-tinstance-nulls
Updated comment
Followed data flow for Column.getType(), not null
Followed data flow: Parameter.getType(), not null
Followed data flow: RowsBuilder.tInsts: not null
Followed data flow: RowType.typeAt: nullable

This might mean that some of those previous commits were wrong and
it could be null
Removed/updated null tinstance comments

either I figured it out, or I gave up and am putting it on trello

some things just aren't worth it.
A bit more comment cleanup
Added comment to TInstance
merge ScottDugas: Figure out TInstance=null situation

Merge pull request #1528 from ScottDugas/sql-layer/fix-tinstance-nulls
https://github.com/FoundationDB/sql-layer/pull/1528