The full release notes are here.

Due to the fact the Release Maintainer does not have access to the download.koha.org site (don’t ask) it is hosted at the koha-fr.org site until someone at Liblime puts it in the right place.

If you are familiar with git you can upgrade that way

git fetch
git reset v3.00.05
export KOHA_CONF=/path/to/koha-conf.xml
export PERL5LIB=/path/to/src
perl installer/data/mysql/updatedatabase.pl
cd misc/translation
install-code.pl yourlanguage