Fix doc for <participating-org>

The documentation mentioned specifying @identifier but should be @ref
Merge pull request #40 from rolfkleef/master

Fix doc for <participating-org>
Changes schema documentation about the percentage attribute.

Since 1.03 this has been changed to be a decimal value.
Reflects changes for the 1.03 release

Needed to change dates, versions and spelling of organisation - including the filename.
Merge pull request #47 from IATI/readme-update

Reflects changes for the 1.03 release
Merge branch 'master' into dc1.04