ChangeLog: Add entry for 2.1.0 [skip ci]
ChangeLog: Add entry for 2.1.0 [skip ci]

Aloomaio/pymssql,pymssql/pymssql,bladams/pymssql,klothe/pymssql,bladams/pymssql,Aloomaio/pymssql,ramiro/pymssql,Aloomaio/pymssql,klothe/pymssql,zerolugithub/pymssql,pymssql/pymssql,bladams/pymssql,zerolugithub/pymssql,ramiro/pymssql,ramiro/pymssql,zerolugithub/pymssql,JimDennis/pymssql,JimDennis/pymssql,JimDennis/pymssql,klothe/pymssql