brew-graph: improve formatting.

This commit adds additional formatting options to the graph. Most noticeable is a top-to-bottom layout (rather than the previous left-to-right), and nicer fonts on everything.

More subtly, the ranking mechanism has been updated so that the "Safe to Remove" cluster is always at the highest rank (fixing a bug where non-leaf nodes could have been placed next to it,) and added better margins and padding. The rank separation was also decreased for a more compact graph.

Under the hood, the GraphViz output code was updated to support attributes with a list of sub-attributes (for example, 'graph [fontsize="11", fontname="Helvetica"]') and to not put quotes around HTML-like labels in clusters.

Closes #26651.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
libcoap: C implementation of CoAP (new formula)

Closes #24721.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
elixir 0.12.4

Closes #26652.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
wireshark: add option to install library headers

These library headers are needed for 3rd party plug-ins like dissectors.

Closes #25400.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
ddar 1.0 (new formula)

Closes #26591.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
docker: add bash/zsh completion.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
docker: update 0.8.0 bottle.

Closes #26654.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
osmium: add to blacklist.

References #12652.
Return only open issues in GitHub.issues_for_formula
Drop unnecessary type check, we never pass a Formula instance
Drop TODO that nobody has ever worked on
Let the API do more work for us