Bare minimum for making MSSQL be recognized by Trac. Requires the following initenv:

trac-admin /PATH/TO/demo initenv --inherit=/path/to/mssql_enabler.ini demo mssql://SERVER/DB

where mssql_enabler.ini:

[components]
mssql_backend.* = enabled
Added init_db to remove "AttributeError: 'MSSQLConnector' object has no attribute 'init_db'"
Solving "AttributeError: 'MSSQLConnector' object has no attribute 'get_connection'"
Solving "NameError: global name 'MSSQLConnection' is not defined".
Solved "TypeError: Can't instantiate abstract class MSSQLConnection with abstract methods cast, concat, drop_table, get_column_names, get_last_id, get_table_names, like, like_escape, prefix_match, prefix_match_value, quote, update_sequence".

Also removed ODBConnection class.
Switched from pyodbc to pymssql.
Now SQL statements can be executed against an SQL Server.
Now a new instance can be initialized through initenv.
Basic working setup. Not tested beyond creating a single ticket in an old VP board. Addresses a problem where pymssql requires tuples in queries.
Switched from pyodbc to pymssql.
Pymssql looks like a livelier community and the project targets MS SQL specifically rather than the ODBC standard. For other databases we'll use trac's default plugins.
Solves "AttributeError: 'MSSQLConnector' object has no attribute 'get_exceptions'"
Merge branch 'reset' of https://github.com/Reposoft/trac-mssql.alt into reset
SQL Server requires different quoting of custom fields.
Merge branch 'reset' now that it has basic functionality.