Add .clang-format and apply format to all source files

src/.clang-format

src/api-server/api/IndividualSMPolicyDocumentApi.cpp

src/api-server/api/IndividualSMPolicyDocumentApi.h

src/api-server/api/SMPoliciesCollectionApi.cpp

src/api-server/api/SMPoliciesCollectionApi.h

src/api-server/impl/IndividualSMPolicyDocumentApiImpl.cpp

src/api-server/impl/IndividualSMPolicyDocumentApiImpl.h

src/api-server/impl/SMPoliciesCollectionApiImpl.cpp

src/api-server/impl/SMPoliciesCollectionApiImpl.h

src/api-server/model/AccNetChId.cpp

src/api-server/model/AccNetChId.h

src/api-server/model/AccNetChargingAddress.cpp

src/api-server/model/AccNetChargingAddress.h

src/api-server/model/AccessTokenErr.cpp

src/api-server/model/AccessTokenErr.h

src/api-server/model/AccessTokenReq.cpp

src/api-server/model/AccessTokenReq.h

src/api-server/model/AccessType.cpp

src/api-server/model/AccessType.h

src/api-server/model/AccuUsageReport.cpp