All vbox objects are child objects from the nsISupports in vbox's
C++ API version. Since the CAPI is generated from the C++ API, I
kept their relationship here, by the definitations below:

typedef struct nsISupports nsISupports;
typedef nsISupports IVirtualBox;
typedef nsISupports ISession;
and so on...

So, when calling the API from nsISupports, we don't need to do
typecasting, and things work still work well.

Introduce vbox_uniformed_api to deal with version conflicts. Use
vbox_install_api to register the currect vboxUniformedAPI with
vbox version.

vboxConnectOpen has been rewritten.

Laine Stump noted on IRC that syntax check wasn't flagging his
typo of 'i= 0'.  This fixes it.

* build-aux/bracket-spacing.pl: Tighten 'space around =' rule.
* src/storage/storage_backend.c
(virStorageBackendCreateExecCommand): Fix offenders.
* src/util/virnuma.c (virNumaGetDistances): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotDeleteMetadataOnly)
(vboxNetworkGetXMLDesc): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainLookupByName):
Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>