i18n-ja: synchronized with
f493c2f67430
i18n: fix non-matching 1st line indentations
When generating documentation, indentation must match for getting the same
view for translated messages. Often an output is generated anyway, but it
can look different. When a syntactically wrong indentation change is done,
runrst will fail (this is detected by test-gendoc.t).
Fix the simple places. When translation knowledge is necessary, the entry is
marked as fuzzy (and therefore skipped when generating translations). A
translator can fix it later.