Fine tune px_save(path = ".R") so all tests cases passes

[johan-ejstrud]

There are some tests cases that are commented out because there are small (mostly insignificant) differences between the original px object and the one create by the R script.

pxmake/tests/testthat/test-74-pxsave-to-R-preserves.R

Lines 42 to 53 in 88aa4f7

	# A couple of tests doens't work, but the functionality is 80 there
	# UNITS in wrong because of (#364)
	# expect_equal_all_px_element(px(get_px_file_path('CONTVARIABLE')))
	# expect_equal_all_px_element(px(get_px_file_path('CONTVARIABLE_multiple_languages')))
	# TITLE differ, which is fine ("" vs NULL)
	# TIMEVAL differ, easy fix
	# expect_equal_all_px_element(px(get_px_file_path('no_timeval_or_codes2')))
	# Something about TIMEVAL causes problems
	# expect_equal_all_px_element(px(get_px_file_path('PRXPRISH')))