Resolve "extend worker class"

Closes #183 (closed)

smash/web/forms/__init__.py

-from forms import WorkerAddForm, \
-    WorkerEditForm, AppointmentDetailForm, AppointmentEditForm, AppointmentAddForm, VisitDetailForm, VisitAddForm, \
-    ContactAttemptForm, ContactAttemptEditForm, KitRequestForm, StatisticsForm, AvailabilityAddForm, \
+from worker_form import WorkerForm
+from forms import VisitDetailForm, \
+    VisitAddForm, KitRequestForm, StatisticsForm, AvailabilityAddForm, \
     AvailabilityEditForm, HolidayAddForm
+from contact_attempt_forms import ContactAttemptAddForm, ContactAttemptEditForm
+from appointment_form import AppointmentDetailForm, AppointmentEditForm, AppointmentAddForm
 from study_subject_forms import StudySubjectAddForm, StudySubjectDetailForm, StudySubjectEditForm
 from subject_forms import SubjectAddForm, SubjectEditForm, SubjectDetailForm
 from voucher_forms import VoucherTypeForm, VoucherTypePriceForm, VoucherForm
 
-__all__ = [StudySubjectAddForm, StudySubjectDetailForm, StudySubjectEditForm, WorkerAddForm, WorkerEditForm,
+__all__ = [StudySubjectAddForm, StudySubjectDetailForm, StudySubjectEditForm, WorkerForm,
            AppointmentDetailForm, AppointmentEditForm, AppointmentAddForm, VisitDetailForm, VisitAddForm,
-           ContactAttemptForm, ContactAttemptEditForm, KitRequestForm, StatisticsForm, AvailabilityAddForm,
+           ContactAttemptAddForm, ContactAttemptEditForm, KitRequestForm, StatisticsForm, AvailabilityAddForm,
            AvailabilityEditForm, HolidayAddForm, SubjectAddForm, SubjectEditForm, SubjectDetailForm, VoucherTypeForm,
            VoucherTypePriceForm, VoucherForm]