Add “Maximum Speed” to analysis sidebar

It shows the distribution of maximum speeds for all ways on the
current route (if that data is available, otherwise it’s summed up
under “unknown”).

`maxspeed:forward` and `maxspeed:backward` is respected in conjunction
with `reversedirection`.

Hovering/clicking table rows to highlight matching segments on the
route work the identical to the other analysis tables.

Additionally, all tags in the analysis tab (way type, surface,
smoothness) are translateable now. The values were added to `en.json`.

Some HTML is rendered with template literals now, instead of
concatenating strings.

Variable declarations were changed from `var` to `const`/`let`.

css/style.css

@@ -350,10 +350,6 @@ table.dataTable.track-analysis-table tfoot td {
     padding-top: 4px;
 }
 
-.track-analysis-title {
-    text-transform: capitalize;
-}
-
 .track-analysis-distance {
     text-align: right;
 }