Merge pull request #57 from rnikander/master

Fixed some formatting and grammatical errors.
Update exceptions.md
Merge pull request #58 from amakeev/patch-1

typo fixed in exceptions.md
One more tweet
HttpServlet Tutorial and updates to tutorial template layout
Merge remote-tracking branch 'origin/master'
Removed extra title in Tutorials index.
Updated Twitter Tips
Fixed broken link on tutorial source.
Fixed some headers in tutorials and removed extra titles.
Removed extra lines
minor wording adjustment on note for tutorial
Minor corrections to all tutorials
Added new event in Sydney Australia and Norway
Missing return type added
Merge pull request #60 from JetBrains/idioms-fix

Missing return type added
Fixed some broken links and typos, and removed <error> tags, which do not render in current site.