browser items parent (moving to thread) fix (crash when dragging postgres layer)
[processing] fixed handling of source strings in ogr algorithms
[processing] indentation fix
dxf export: fix display of check states on upper levels
browser items moveToThread() also children
QgsMimeDataUtils::Uri fixed crash on empty data
Improve filtering by schema for postgres connections in browser

Results in much faster display and refresh of postgres tables

Also:
- ensure browser correctly respects postgres connection settings
- add schema comment tooltip and refresh context menu item
- make postgres connections less noisy in debug logs
Update comment to match with code
oracle provider: fix evaluation of default values