First test helpers tests (#1369)

* Removed unused advanceToBlock.

* Added advanceBlock tests.

* Fixed advanceToBlock tests.

* Added single argument tests.

* Finished inLogs tests.

* Fixed linter errors.

* Fixed linter errors.

contracts/mocks/EventEmitter.sol

@@ -0,0 +1,62 @@
+pragma solidity ^0.4.24;
+
+contract EventEmitter {
+  event Argumentless();
+  event ShortUint(uint8 value);
+  event ShortInt(int8 value);
+  event LongUint(uint256 value);
+  event LongInt(int256 value);
+  event Address(address value);
+  event Boolean(bool value);
+  event String(string value);
+  event LongUintBooleanString(
+    uint256 uintValue,
+    bool booleanValue,
+    string stringValue
+  );
+
+  function emitArgumentless() public {
+    emit Argumentless();
+  }
+
+  function emitShortUint(uint8 value) public {
+    emit ShortUint(value);
+  }
+
+  function emitShortInt(int8 value) public {
+    emit ShortInt(value);
+  }
+
+  function emitLongUint(uint256 value) public {
+    emit LongUint(value);
+  }
+
+  function emitLongInt(int256 value) public {
+    emit LongInt(value);
+  }
+
+  function emitAddress(address value) public {
+    emit Address(value);
+  }
+
+  function emitBoolean(bool value) public {
+    emit Boolean(value);
+  }
+
+  function emitString(string value) public {
+    emit String(value);
+  }
+
+  function emitLongUintBooleanString(
+    uint256 uintValue,
+    bool booleanValue,
+    string stringValue)
+  public {
+    emit LongUintBooleanString(uintValue, booleanValue, stringValue);
+  }
+
+  function emitLongUintAndBoolean(uint256 uintValue, bool boolValue) public {
+    emit LongUint(uintValue);
+    emit Boolean(boolValue);
+  }
+}