A new method, get_unaddable_by_theme_block_types(), has been added to
block_manager class to let themes define, using the unaddableblocks
theme setting, the blocks that won't be displayed in the "Add a block"
list.
For now, only the boost theme uses it, to disable some of the blocks,
like settings, navigation, course_list and section_links (they are still
required for classic).
The Classic theme is being introduced as a Bootstrap 4 replacement
for the older themes based on Bootstrap 2, such as Bootstrapbase,
Clean and More. It is a child theme of Boost, with a navigation
structure similar to the Clean theme.
Co-authored-by: Bas Brands <bmbrands@gmail.com>
Co-authored-by: Michael Hawkins <michaelh@moodle.com>
