Commented out throws declarations that crash clang 3.4.
Made the orig_btree_t struct with entry_is_deletion...entry_size as static methods.  Added FILE_write_file_stream_t, unused.
Removed needless duplicatino of leaf::strprint_leaf and leaf::print.
Removed worthless FILE_write_file_stream_t, used more straightforward templatization to implement strprint_leaf and leaf::print.