Console sidebar improvements

Sidebar:
- Adjust vertical spacing of general section
- Rename 'General' section to 'Router Info' and move ident info to h3 tooltip
  (ticket #1996)
- Replace 'Short Router Info' with a new 'Advanced Router Info' section in
  default advanced sidebar (adds memory usage and clock skew)
- Add optional embedded bandwidth graph (experimental)
- Add optional memory usage bar
- Add optional Advanced Peers section (adds failing and banned peers)
- Add Help link to 'I2P Internals' section
- Add help page anchored links and troubleshooting to 'Help & FAQ' section
- Add download progress bar for router and plugin updates
- Add 'Advanced Minimal' sidebar configuration
- Add Jobs and Events links to Advanced section
- Add additional reachability states for clockskew and vmcomm (with icons)

Homepage: Add 'Customize Sidebar' link to signpost the feature now that there
  are more optional sections available (ticket #1996)

apps/routerconsole/java/src/net/i2p/router/web/SummaryRenderer.java

@@ -266,7 +266,7 @@ class SummaryRenderer {
                 def.area(dsNames[0], AREA_COLOR, _listener.getRate().getRateStat().getDescription());
                 def.line(dsNames[1], LINE_COLOR, "Events per period");
             */
-            if (hideLegend) 
+            if (hideLegend)
                 def.setNoLegend(true);
             if (hideGrid) {
                 def.setDrawXGrid(false);