Add assemble_circuits() to root namespace (#2159)
Add assemble_circuits() to root namespace (#2159)

The deprecation message for qiskit.compile() says that it is deprecated
and instead qiskit.assemble_circuits() in conjuction with transpile()
should be used instead of calling compile(). However, we never added
assemble_circuits to the root namespace on qiskit so you couldn't
actually call it that way. This commit corrects the oversight and
adds it to the root namespace.
QISKit/qiskit-sdk-py,QISKit/qiskit-sdk-py,QISKit/qiskit-sdk-py