[C2] Xapian: Search results display improvements

[ywarnier]

In Xapian search results,

• titles with accents are shown as escaped HTML characters (looking at the title in the course, it doesn't appear escaped).
• the highlighted words are surrounded by spaces, which divides words if the searched result is within a word. This makes it difficult to read. Example: search for reptile and if a result includes "reptiles", then it it shown as "reptile s"

[christianbeeznest]

It is checked with this commit aa4efcd

Thanks for confirmation.

[ywarnier]

Prefect. Thanks.

[ywarnier]