wikipedia indexing: don't print references to external links like "[1]", just ignore them

git-svn-id: https://languagetool.svn.sourceforge.net/svnroot/languagetool/trunk/languagetool@9731 2fe6a88b-1217-0410-b804-ba6ed01314b8
wikipedia indexing: catch Exception so one problem doesn't stop the whole indexing process; some optimization

git-svn-id: https://languagetool.svn.sourceforge.net/svnroot/languagetool/trunk/languagetool@9732 2fe6a88b-1217-0410-b804-ba6ed01314b8