changed ractivejs.org to ractive.js.org (as well as github name)

[ceremcem]

Fixes ractivejs/ractivejs.github.io#138

Note: Not tested. I simply run the following commands in the repo:

find . -type f -exec sed -i 's/ractivejs\.org/ractive\.js\.org/g' {} +
find . -type f -exec sed -i 's/docs\.ractive\.js\.org/v0\.x/g' {} +

..then created the PR.

[fskreuz]

This looks good. Just no guarantees that the old links have counterparts in the new since things have moved around.

[ceremcem]

That's one of the possible scenarios where hash routing rocks ❤️

[ceremcem]

Fixed some links that I broke with the previous commits and just redirected all documentation related addresses to current support page by:

find . -type f -exec sed -i 's/https:\/\/v0.x.*/https:\/\/ractive\.js\.org\/support/g' {} +