Small improvements on the mining page UX

- INDEXING_BLOCKS_AMOUNT = 0 disable indexing, INDEXING_BLOCKS_AMOUNT = -1 indexes everything
- Show only available timespan in the mining page according to available datas
- Change default INDEXING_BLOCKS_AMOUNT to 1100

Don't use unfiltered mysql user input

Enable http cache header for mining pools (1 min)

frontend/src/app/app-routing.module.ts

@@ -60,7 +60,7 @@ let routes: Routes = [
         component: LatestBlocksComponent,
       },
       {
-        path: 'pools',
+        path: 'mining/pools',
         component: PoolRankingComponent,
       },
       {
@@ -147,6 +147,10 @@ let routes: Routes = [
             path: 'blocks',
             component: LatestBlocksComponent,
           },
+          {
+            path: 'mining/pools',
+            component: PoolRankingComponent,
+          },
           {
             path: 'graphs',
             component: StatisticsComponent,
@@ -225,6 +229,10 @@ let routes: Routes = [
             path: 'blocks',
             component: LatestBlocksComponent,
           },
+          {
+            path: 'mining/pools',
+            component: PoolRankingComponent,
+          },
           {
             path: 'graphs',
             component: StatisticsComponent,