fix gdb.python to be parallel-safe

fix gdb.python to be parallel-safe

This fixes gdb.python to be parallel-safe, mostly by changing it to
use gdb_remote_download.

Tested on x86-64 Fedora 18.

	* gdb.python/py-error.exp: Use gdb_remote_download.
	* gdb.python/py-mi.exp: Use gdb_remote_download.
	* gdb.python/py-objfile-script.exp: Use standard_output_file.
	* gdb.python/py-prettyprint.exp: Use gdb_remote_download.
	(run_lang_tests): Likewise.
	* gdb.python/py-section-script.c: Use SCRIPT_FILE rather than
	filename.
	* gdb.python/py-section-script.exp: Set SCRIPT_FILE when
	compiling.  Use gdb_remote_download.  Update some tests.
	* gdb.python/py-strfns.exp (test_strfns_core_file): Use
	standard_output_file.
	* gdb.python/py-typeprint.exp: Use gdb_remote_download.
	* gdb.python/py-frame-args.exp: Use gdb_remote_download.
	* gdb.python/py-framefilter-mi.exp: Use gdb_remote_download.
	* gdb.python/py-framefilter.exp: Use gdb_remote_download,
	standard_output_file.