Make receiving keys from a keyserver work with GnuPG 2.1
* src/gpaimportop.h (_GpaImportOperation): Add field source2. (_GpaImportOperationClass): Change prototype of get_source and all callers. * src/gpaimportop.c (gpa_import_operation_finalize): Release source2 var. (gpa_import_operation_idle_cb): Use import_keys if source2 is set. (key_import_results_dialog_run): Use modern info functions. * src/gpaimportserverop.c (MAX_KEYSEARCH_RESULTS): New. (search_keys): New. (gpa_import_server_operation_get_source): Make use of source2. * src/gparecvkeydlg.c (gpa_receive_key_dialog_init): Change prompt for gnupg 2.1.0.
Passing the instance variable to several fucntions of the class was a
bit weird. Thus changed to use it direct.