Improvement to result display in smart search

Results are truncated to a number of characters from the begining, so unless your query falls there, you won't see it in the results view, which may confuse the user who did the search.

This improves the truncation so that characters around the search query are shown. If it was the last word in the article, then chosen amount of characters before it will be shown (or after if it was at the begining), otherwise it aims for the search query to be in the middle of excerpt for optimal understanding.

If the match was not in the body of the description, then the first XXX characters will be shown like before.

Maybe such function would be useful to add to JHtml.string?
Update default_result.php
Update joomla.sql
Update joomla.sql
Update joomla.sql
Update joomla.sql
Revert "Update joomla.sql"

This reverts commit 774a31f6b3396840f73d145be5cb3da14a2d1396.
Revert "Update joomla.sql"

This reverts commit a4a55361a07c09d9dca97520056a7d1d02ffc034.
Revert "Update joomla.sql"

This reverts commit 38600728c88c46b01f059fefefebaee688c9bc5e.
Revert "Update joomla.sql"

This reverts commit 774a31f6b3396840f73d145be5cb3da14a2d1396.
[bug][32792] Fixed errors with Hathor and Quick Icons. Closes #3986
[imp][25225] "File" cache handler should complain if the cache directory doesn't exist. Fixes #3999
[bug][33917] Direct URL asscess of a menu item bypasses Viewing Permissions. Fixes #3984
[bug][33473] itms-services schema not correctly handled. Fixes #3992
[cs][32433] Removed Unused Variables and Correct DocBlock with staging. Closes #3082
Codestyle
[bug][31951] com_admin help - search not functioning. Fixes #3998
[imp][33654] Fix the border on a chosen dropdown. Fixes #4000.
Merge pull request #3055 from chivitli/staging

[#33290] Improvement to result display in smart search