Merge pull request #674 from kgrz/master

Chinese, Korean, Russian Markdown fixes
Adds failing test for after filters
Fixes #673 and adds additional test for before filter
Merge pull request #678 from nesquena/fix_exception_handling_for_filters

Fix exception handling for filters
fix HEADER_VALUE_WITH_PARAMS regex and added a test case for this regex.
add support for mime types with dots, hyphens and plus signs.
Merge pull request #679 from patriciomacadden/provides

Fix HEADER_VALUE_WITH_PARAMS regex and added a test case for this regex.
Cleanup unused variables
Just some typos, here and there!
Merge pull request #681 from vipulnsward/cleanup_typos

Just some typos, here and there!
update changes
fix headings in German readme
add toc to german readme
fix headings in russian readme, I hope
Use |_| instead of vars; fix typo
Merge pull request #680 from vipulnsward/cleanup_tests

Cleanup unused variables
add 1.2.9 changes
Merge branch 'master' of github.com:sinatra/sinatra
add 1.3.6 changes
set release date