Introduce `term_template` param to `get_the_taxonomies()`.

This parameter allows theme and plugin authors to specify the formatting they
would like on the term links as they are parsed into the taxonomy list.

Props hereswhatidid, dlh, davidjlaietta.
See #27238.

git-svn-id: https://develop.svn.wordpress.org/trunk@30209 602fd350-edb4-49c9-b593-d223f7449a82
Improve docblocks for `get_the_taxonomies()` and `the_taxonomies()`.

* In `the_taxonomies()`, only document those arguments that are specific to the function. Arguments shared with `get_the_taxonomies()` should be documented in the later function's docblock.
* Add $args hash documentation to `get_the_taxonomies()`.
* Remove the redundant default argument definition in `the_taxonomies()`.

Fixes #27238.

git-svn-id: https://develop.svn.wordpress.org/trunk@30210 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Fifteen: prevent a flash of visible sub menus before scripts load.

Props mattwiebe, aferica, fixes #30056.



git-svn-id: https://develop.svn.wordpress.org/trunk@30211 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Fifteen: add a fallback icon for social links where we don't have an icon

Props iamtakashi, fixes #30148



git-svn-id: https://develop.svn.wordpress.org/trunk@30212 602fd350-edb4-49c9-b593-d223f7449a82
Twenty Fifteen: nicer styles for playlists.

Props iamtakashi, fixes #30163



git-svn-id: https://develop.svn.wordpress.org/trunk@30213 602fd350-edb4-49c9-b593-d223f7449a82