- remove /etc/vservers S_CAPS parsing; this is not really well supported

- remove /etc/vservers S_CAPS parsing; this is not really well supported
  right now under the new 0.30.208 framework, and we don't currently use
  it now that we have Proper. Should be relatively straightforward to
  restore if necessary, by using vc_text2cap() instead.
- print better error messages
- use new vc_ctx_create() syscall. Correct the old "legacy" way of
  creating a context and reducing its capabilities for posterity, but
  don't actually compile it. For the record, apparently you have to
  reduce the capabilities in a second call to vc_new_s_context() with
  VC_SAMECTX; see kernel/vserver/context.c under "dirty hack for
  capremove".