Chris Shoemaker's gnc-trace patch.

[Derek Atkins]

Log Message:
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Chris Shoemaker's gnc-trace patch.

	* src/engine/gnc-trace.[ch]:
	  - Recent use of malloc in gnc-trace breaks my compile, use g_malloc
	  - Fix leak of filename mem
	  - add indenting of trace file according to ENTER/LEAVE stack depth
	  - have ENTER report file name of function along with function name

Modified Files:
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    gnucash:
        ChangeLog
    gnucash/src/engine:
        gnc-trace.c
        gnc-trace.h