Small bug fix

Hi,

I have been experimenting with libofx and GNUCash to try and load 
statements from an online broker account. One of the statements caused 
the program to hang, and the same happened on running ofxdump on the 
same statement. This appears to be caused by code in 
ofx_container_transaction.cpp which steps up through parent elements to 
find a STATEMENT element. The code was caught in a loop, it always took 
the parent of the same container instead of looping through all parents.

diff ofx_container_transaction.cpp 
../../libofx_cvs/libofx/lib/ofx_container_transaction.cpp
46,47c46
<       tmp_parentcontainer=tmp_parentcontainer->parentcontainer;
<
---
 >       tmp_parentcontainer=parentcontainer->parentcontainer;

I still have some problems with the import, commisions are not brought 
into gnucash for example, and ofxdump gives many errors along the lines of:
LibOFX ERROR: WRITEME: COMMISSION (1) is not supported by the INVESTMENT 
container
If it would be useful I can post a more complete bug report and a 
cleaned version of the .ofx file, once I have a chance to find and 
remove private info from it.

I am a bit hazy on which areas GnuCash, libofx and OpenSP are 
responsible for when imprting a file. I take it OpenSP just gives a list 
of tags which match the provided DTD. But if an element isn't recognized 
in LibOFX, does it just have to be added to the library, or does GnuCash