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Refs #177
Add hooks in core builder templates.
Add filter for changing data when adding builder section.
Remove confusing comment.
Allow section data to be filtered.
Filter ttfmake_will_be_builder_page().
Cleanup and filter ttfmake_load_section_template().
Filter ttfmake_get_wp_editor_id().
Filter ttfmake_get_section_name().
Code style cleanup.
Filter ttfmake_get_image().
Filter ttfmake_get_image_src().
Filter ttfmake_get_placeholder_image().
Add hooks to save.php.
Code style cleanup.
Add hooks to section-definitions.php.
Add hooks to section-front-end-helpers.php.
Codestyling.
Remove unnecessary variable.
Code styling.