SortByDirection: due to relatively slow performance of AddRange library method, check if sorting changed the sort order of the articles and only clear and readd articles to list box if changed

Performance of check for change is 2 ms per 50k articles, AddRange just under 400 ms for same list

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10348 5227b50d-9349-4574-b055-4b0a7525e11c
Fix previous

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10349 5227b50d-9349-4574-b055-4b0a7525e11c
Update code comment

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10350 5227b50d-9349-4574-b055-4b0a7525e11c
RemoveDuplicatesNew: avoid performance penalty of AddRange if deduplication didn't remove any articles

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10351 5227b50d-9349-4574-b055-4b0a7525e11c
RemoveDuplicatesOld: performance improvement by using AddRange (1 second saved per 10k articles)

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10352 5227b50d-9349-4574-b055-4b0a7525e11c
RemoveDuplicatesOld: avoid performance penalty of AddRange if deduplication didn't remove any articles

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10353 5227b50d-9349-4574-b055-4b0a7525e11c
Filter namespace: avoid performance penalty of AddRange if filter didn't remove any articles

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10354 5227b50d-9349-4574-b055-4b0a7525e11c
FilterNonMainArticles: improve performance when number of articles to be removed is < 1% of total

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10355 5227b50d-9349-4574-b055-4b0a7525e11c
Find mode: for performance limit tree view to first 500 results

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10356 5227b50d-9349-4574-b055-4b0a7525e11c
Text file loader: tweak regex to reduce backtracking

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10357 5227b50d-9349-4574-b055-4b0a7525e11c
Fix RemoveSelected change from 10343 to use right option when first article is included in selection

git-svn-id: svn://svn.code.sf.net/p/autowikibrowser/code/AWB@10358 5227b50d-9349-4574-b055-4b0a7525e11c