[v1.0.3-.1.0] Create a scheme based on another.

Full changelogs:

_v1.0.3 - 01.05.2013:_
- [Fixed bug] Due to a missing underscore on the main page of the
editor, you had to reselect your language every time you visited that
main page (as the missing underscore prevented the language cookie from
being recognized).
- [Fixed bug] Since v1.0.2, it was impossible to View a Scheme with an
apostrophe in its name/author name (there again, thanks to Piki1802 for
helping me realizing the bug was present).

_v1.1.0 - 02.05.2013:_
- [New feature] It is now possible to create a scheme based on an
existing one.
- [New feature] It is now possible to create a scheme without saving it
on the server and in the database.
- [Change] The "Select Another Language" links are no longer
translatable. These links are a stopgap until I implement flags anyway.
[v1.1.0] Dutch translation completion.

Piki1802 has completed his Dutch translation (the Changelog doesn't need
to be translated).