Added MySQL Data Compare

Pretty much just a clone of MySQL Compare with some words switched around.
Added SQL Doc

There isn't a page which is explicit about the OSS licensing and pricing, so I've just pointed to the product page for now.
Added SQL Test

No official announcement of the OSS support, so I've pointed to the product page for now.
Added SQL Dependency Tracker

Linking to Product page, as there's no other announcement at the moment.
Added SQL Data Generator

No OSS support announcement, so I've pointed this to the product page for now.
Updated Red Gate "Any" platform tags to "SQL"

Several of the Red Gate tools were tagged as being for "any" platform. They're for any development platform, but they're very much for SQL / MySQL / Oracle DB platforms.
Updated outstanding Red Gate tools to reference OSS blog post.

SQL Doc, SQL Data Generator, SQL Dependency Tracker and SQL Test now all have a reference blog post to confirm that they're free to OSS projects.
Merge pull request #16 from camassey/gh-pages

Added some more Red Gate tools, and updated some Platform tags