Review fixups

Author: Yasumoto

Sources/Prometheus/MetricTypes/Counter.swift

@@ -73,10 +73,11 @@ public class Counter<NumType: Numeric, Labels: MetricLabels>: Metric, Prometheus
                 var val = self.metrics[labels] ?? self.initialValue
                 val += amount
                 self.metrics[labels] = val
+                done(val)
             } else {
                 self.value += amount
+                done(self.value)
             }
-            done(self.value)
         }
     }
 

Sources/Prometheus/MetricTypes/Gauge.swift

@@ -109,9 +109,7 @@ public class Gauge<NumType: Numeric, Labels: MetricLabels>: Metric, PrometheusHa
     ///     - done: Completion handler
     ///
     public func inc(_ labels: Labels? = nil, _ done: @escaping (NumType) -> Void = { _ in }) {
-        self.inc(1, labels) { value in
-            done(value)
-        }
+        self.inc(1, labels, done)
     }
 
     /// Decrements the Gauge
@@ -141,9 +139,7 @@ public class Gauge<NumType: Numeric, Labels: MetricLabels>: Metric, PrometheusHa
     ///     - labels: Labels to attach to the value
     ///
     public func dec(_ labels: Labels? = nil, _ done: @escaping (NumType) -> Void = { _ in }) {
-        self.dec(1, labels) { value in
-            done(value)
-        }
+        self.dec(1, labels, done)
     }
 
     /// Gets the value of the Gauge

Sources/Prometheus/MetricTypes/Summary.swift

@@ -1,5 +1,3 @@
-import Dispatch
-
 /// Default quantiles used by Summaries
 public var defaultQuantiles = [0.01, 0.05, 0.5, 0.9, 0.95, 0.99, 0.999]