odfmetadata4: #i108911#: configure.in: enable with-system-redland:

 based on patch by cmc.
 no patches are required for redland any more, so enable system redland.
 minimum version is redland 1.0.8.

redland/README

@@ -22,7 +22,8 @@ Libraries: libraptor, librasqal, librdf
 Patches:
 There are several patches, most of which contain only hacks to get it to
 build with OOo build system.
-There are also 3 patches that fix bugs in redland and are of general interest:
+There used to be also 3 patches here that fix bugs in redland and ought to be
+of general interest:
 - redland-1.0.8.patch.free_null:
   redland destructor functions don't check if argument is NULL
 - redland-1.0.8.patch.storage_hashes_context_serialize_get_statement:
@@ -31,4 +32,7 @@ There are also 3 patches that fix bugs in redland and are of general interest:
 - redland-1.0.8.patch.storage_hashes_list_duplicates:
   hashes, list storage: if contexts are enabled, then it is possible to add
                         duplicate statements
+Attempts to upstream these patches failed for reasons upstream kept to
+themselves.  Now these patches are replaced with workarounds in unoxml.
+Note to future maintainers: work around redland bugs in client code.