Make separate examples proper R-style demos

Change-Id: I0ac284cfc1d0c508030c91189f260299680c1485
diff --git a/demo/00Index b/demo/00Index
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index 0000000..7fe8aff
--- /dev/null
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+frequenciesOverTime       Plot frequency of query expressions over time
+frequenciesOverDomains    Box plot frequency of query expressions per topic domain
+conditionsOverTime        Plot frequency of query expressions over time under different conditions
+alternativesOverTime      Plot proportion of alternative spellings/variants over time
+regional                  Map plot regional frequencies of query expression