gnucash-docs from Office project

需要 openSUSE Tumbleweed ，用 root 執行：

zypper addrepo https://download.opensuse.org/repositories/Office/openSUSE_Tumbleweed/Office.repo
zypper refresh
zypper install gnucash-docs

需要 16.0 ，用 root 執行：

zypper addrepo https://download.opensuse.org/repositories/Office/16.0/Office.repo
zypper refresh
zypper install gnucash-docs

需要 openSUSE Leap 15.6 ，用 root 執行：

zypper addrepo https://download.opensuse.org/repositories/Office/openSUSE_Leap_15.6/Office.repo
zypper refresh
zypper install gnucash-docs