UI: Add caching to overview recent transactions NOTE: Resizing window can result in a significant number of repaint actions, causing the same recent transactions to be repeatedly parsed.  This commit ensures transactions are only parsed one and then added to a temporary cache.
UI: Add caching to overview recent transactions
NOTE: Resizing window can result in a significant number of repaint actions, causing the same recent transactions to be repeatedly parsed.  This commit ensures transactions are only parsed one and then added to a temporary cache.

OmniLayer/omnicore,OmniLayer/omnicore,OmniLayer/omnicore,OmniLayer/omnicore,OmniLayer/omnicore,OmniLayer/omnicore