Add support for HTML import

Packages describing “html” as local USE flag

Package “html” Flag Description
app-office/lyx Add support for HTML import
media-video/google2srt Install HTML documentation
app-doc/csound-manual Install HTML documentation
app-doc/kicad-doc Generate documentation in HTML format
app-doc/pms Generate and install PMS as .html as well
app-doc/pms-bin Install PMS as .html as well
app-doc/tldp-howto Install multi-chapter HTML docs
dev-libs/fcgi Install HTML documentation
dev-db/pgrouting Install HTML formatted documentation
dev-python/translate-toolkit Support conversion between po and html files
dev-qt/qt-docs Install documentation in HTML format
net-misc/chrony Install HTML documentation
media-video/vdr Install HTML documentation
net-analyzer/bwm-ng Enable html output
sci-mathematics/why3-for-spark Build HTML documentation
net-misc/hylafaxplus Convert faxes into html email
sys-cluster/slurm Build html documentation

All packages providing a “html” USE flag (12)