(ko) Fix and retouch news 2013-12-21-semantic-versioning-after-2-1-0.md
Corrected capitalization for <ru/index.html>. 

Capitalized letters without reason are good for style.
Inserted a missing comma for Russian (ru).
Corrected spelling for phrases in <ru/examples/cities.md>.
Fix Japanese mirror server (RingServer) addresses at downloads [en]
Use named references instead of numeric ones at en/downloads [en]
Merge pull request #543 from arbox/patch-3

Corrected spelling for phrases in <ru/examples/cities.md>.
Merge pull request #541 from arbox/patch-1

Corrected capitalization for <ru/index.html>.
Merge pull request #542 from arbox/patch-2

Inserted a missing comma for Russian (ru).
Merge pull request #544 from makimoto/en-fix-mirror-sites

Use named references instead of numeric ones at en/downloads [en]
Update security page (id)
Fix indentation (de)
Small fixes on downloads page (en)
Small fixes on downloads page (es)
Fix Decimal -> Rational in 2.1.0 release announce [all]
Update index.md

Corrected a typo at line 114: changed 'Match' with 'Math'
Update index.md

Updated some outdated link and description, corrected some typo, and made the translation from english more fluent.
Fix mirror site list of downloads in es. it, ko, pl, zh_cn and zh_tw
Update ruby-core page (it)

Update translation (now pertinent to the EN ruby-core page), fix some typo, add How to use GitHub.
Update documentation page (it)

Add Dash tool for far Mac OS X