Movable datasets support

src/sampleconf/recoll.conf

@@ -571,6 +571,31 @@ logfilename = stderr
 # the log... values.</descr></var>
 #daemlogfilename = /dev/null
 
+# <var name="orgidxconfdir" type="dfn">
+#
+# <brief>Original location of the configuration directory.</brief>
+# <descr>This is used exclusively for movable datasets. Locating the
+# configuration directory inside the directory tree makes it possible to
+# provide automatic query time path translations once the data set has
+# moved (for example, because it has been mounted on another
+# location).</descr></var>
+#orgidxconfdir = 
+
+# <var name="curidxconfdir" type="dfn">
+#
+# <brief>Current location of the configuration directory.</brief>
+# <descr>Complement orgidxconfdir for movable datasets. This should be used
+# if the configuration directory has been copied from the dataset to
+# another location, either because the dataset is readonly and an r/w copy
+# is desired, or for performance reasons. This records the original moved
+# location before copy, to allow path translation computations.  For
+# example if a dataset originally indexed as '/home/me/mydata/config' has
+# been mounted to '/media/me/mydata', and the GUI is running from a copied
+# configuration, orgidxconfdir would be '/home/me/mydata/config', and
+# curidxconfdir (as set in the copied configuration) would be
+# '/media/me/mydata/config'.</descr></var>
+#curidxconfdir = 
+
 # <var name="idxrundir" type="dfn">
 #
 # <brief>Indexing process current directory.</brief> <descr>The input