[SDK-68] Improving SDK logging (#408)

* Improving SDK logging

* Disable all logging except errors by default
* Add support for log levels

* Aligning with design doc

* Adding OFF level, fixing tests

* Additional fixes for tests

* Fix unit tests for PowerMock

* Fixing docs

Co-authored-by: Hristo Borisov <[email protected]>

Author: milos1290

AndroidSDKCore/src/main/java/com/leanplum/ActionContext.java

@@ -204,7 +204,7 @@ public <T> T objectNamed(String name) {
       return VarCache.getMergedValueFromComponentArray(
           VarCache.getNameComponents(name), args);
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
       return null;
     }
   }
@@ -221,7 +221,7 @@ public String stringNamed(String name) {
     try {
       return fillTemplate(object.toString());
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
       return object.toString();
     }
   }
@@ -282,7 +282,7 @@ public InputStream streamNamed(String name) {
       }
       return stream;
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
       return null;
     }
   }
@@ -301,7 +301,7 @@ public boolean booleanNamed(String name) {
       }
       return convertToBoolean(object.toString());
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
       return false;
     }
   }
@@ -334,7 +334,7 @@ public Number numberNamed(String name) {
       }
       return Double.valueOf(object.toString());
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
       return 0.0;
     }
   }
@@ -391,7 +391,7 @@ public void variablesChanged() {
             try {
               Leanplum.triggerMessageDisplayed(actionContext);
             } catch (Throwable t) {
-              Util.handleException(t);
+              Log.exception(t);
             }
           }
         });
@@ -401,7 +401,7 @@ public void variablesChanged() {
       }
       return true;
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
     }
     return false;
   }
@@ -525,7 +525,7 @@ public void runTrackedActionNamed(String name) {
       }
       runActionNamed(name);
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
     }
     Leanplum.countAggregator().incrementCount("run_tracked_action_named");
   }
@@ -559,7 +559,7 @@ public void trackMessageEvent(String event, double value, String info,
         LeanplumInternal.track(event, value, info, params, requestArgs);
       }
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
     }
   }
 
@@ -575,15 +575,15 @@ public void track(String event, double value, Map<String, Object> params) {
         LeanplumInternal.track(event, value, null, params, requestArgs);
       }
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
     }
   }
 
   public void muteFutureMessagesOfSameKind() {
     try {
       ActionManager.getInstance().muteFutureMessagesOfKind(messageId);
     } catch (Throwable t) {
-      Util.handleException(t);
+      Log.exception(t);
     }
   }