WebSearch: asciification of `oe` grapheme

* Properly asciifies `oe` grapheme.  (closes #1582)

* NOTE Please reindex if your records may contain `oe` UTF-8 graphemes.

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>
Merge branch 'maint-1.0' into maint-1.1

* maint-1.0:
  WebSearch: asciification of `oe` grapheme

Conflicts:
	RELEASE-NOTES
	modules/websearch/lib/search_engine.py
	modules/websearch/lib/search_engine_unit_tests.py

Signed-off-by: Tibor Simko <tibor.simko@cern.ch>