Chore: Improve documentation

Author: amotl

docs/migrate-from-crate-client.md

@@ -33,6 +33,14 @@ from sqlalchemy_cratedb import dialect
 from sqlalchemy_cratedb import ObjectArray, ObjectType, FloatVector, Geopoint, Geoshape
 ```
 
+```python
+# Previous import
+from crate.client.sqlalchemy.compiler import CrateDDLCompiler, CrateTypeCompiler
+
+# New import
+from sqlalchemy_cratedb.compiler import CrateDDLCompiler, CrateTypeCompiler
+```
+
 ```python
 # Previous import
 # from crate.client.sqlalchemy.predicates import match