Rework BB Posts Module Support (custom where?)

[quasel]

Target is to have a similar feature set as the pods shortcode in regards of which pod items are selected for output. The display itself is done int the posts module it's like preparing of a very custom [each] and take care of pagination!

• CPT (some functionality already in there)
• order
• orderby
• where

Ideas:

• don't hide the default post type selector and add "current option"-> Main Query?
• extend the list on the related options / make them dependent on selected post_type?
• always display customize where as it could be applied to posts from relations too

Additionaly look into PP/UABB and their Module ( Advanced Posts / Content Grid )

Add support for all Pods Objects (Users, Taxonomy, ... )

• custom layout -> dynamic changes?

[quasel]

@sc0ttkclark suggest for paging:

• we hook in fl_builder_loop_query_args to always force page 1
• hook in fl_builder_loop_query after the query is setup to 'trick' the query to think it's really on the true page

[quasel]

current solution: Just allow relationships, no pagination, seems there are some issues on BB side as well! (pagination not working on single CPT)

[quasel]

closing in favor of #71 - only thing left is the custom where