Some (very minor) translation string improvements.

Fix superfluous space.
Unify case sensitivity in string that appears multiple times.

gnucash/import-export/csv-imp/gnc-imp-props-price.cpp

@@ -234,7 +234,7 @@ std::string GncImportPrice::verify_essentials (void)
     else if (m_from_commodity == boost::none)
         return _("No 'Commodity from' column.");
     else if (gnc_commodity_equal (*m_from_commodity, *m_to_currency))
-        return _("'Commodity from' can not be the same as 'Currency to'.");
+        return _("'Commodity From' can not be the same as 'Currency To'.");
     else
         return std::string();
 }

libgnucash/core-utils/gnc-filepath-utils.cpp

@@ -673,7 +673,7 @@ static std::string migrate_gnc_datahome()
     if (full_copy)
     {
         migration_msg
-        << bl::translate ("Your gnucash metadata has been migrated .") << std::endl << std::endl
+        << bl::translate ("Your gnucash metadata has been migrated.") << std::endl << std::endl
         /* Translators: this refers to a directory name. */
         << bl::translate ("Old location:") << " " << old_dir.string() << std::endl
         /* Translators: this refers to a directory name. */