add `directory` option to report class

src/@graph/graph.m

src/@graph/write.m

src/@graph/writeGraphFile.m

src/@page/page.m

src/@page/write.m

src/@report/compile.m

src/@report/report.m

src/@report/write.m

src/@report_table/report_table.m

src/@report_table/write.m

src/@report_table/writeTableFile.m

src/@section/section.m

src/@section/write.m

test/createReport.m