add Import button to Memory Viewer

[Jamiras]

Allows importing search results exported from a previous search to be used as the initial state of a new search.

https://discord.com/channels/310192285306454017/310195377993416714/1199805920251744296

For example: If I had narrowed my search results down to four values:

$0056   67
$0058   01
$019F   00
$153A   00

I could export this, and then later import it again, which would initialize a new search containing those four addresses and their captured values. The first filter on "!=" would compare against the 67/01/00/00 values. Then future filters would proceed normally using the values captured from the previous filter.

Similar to loading states, the initial values come from the import (instead of before loading the state) and filters are applied based on the current state (after loading the state/after importing).

NOTE: does not work with ASCII, BitCount or 4-bit searches.