MLOG_ZIP_LIST_START_COPY and MLOG_ZIP_LIST_END_COPY.

btr_compress(): Simplify a debug assertion.

page_zip_compress_write_log(), page_zip_parse_compress(): New functions.

page_cur_parse_insert_rec(): Simplify the code.

page_parse_create_zip(): Removed.

page_create_zip(), page_copy_rec_list_end(),
page_copy_rec_list_start(): Invoke page_zip_compress_write_log().