correct crashing error on block   00000000000997f9fd2fe1ee376293ef8c42ad09193a5d2086dddf8e5c426b56

block:    00000000000997f9fd2fe1ee376293ef8c42ad09193a5d2086dddf8e5c426b56

ths block has some odd transactions that caused my code to crash when trying
to load all balances. I have corrected this by checking if "address" is
defined. Added tests to check.