deleted float operator overloads and added unary operator- to Time
diff --git a/aos/common/time.h b/aos/common/time.h
index a35065d..bc2dc3e 100644
--- a/aos/common/time.h
+++ b/aos/common/time.h
@@ -165,6 +165,12 @@
   Time &operator*=(int32_t rhs);
   Time &operator/=(int32_t rhs);
   Time &operator%=(int32_t rhs);
+  Time &operator%=(double rhs) = delete;
+  Time &operator*=(double rhs) = delete;
+  Time &operator/=(double rhs) = delete;
+  const Time operator*(double rhs) const = delete;
+  const Time operator/(double rhs) const = delete;
+  const Time operator%(double rhs) const = delete;
   #endif
   const Time operator+(const Time &rhs) const;
   const Time operator-(const Time &rhs) const;
@@ -173,6 +179,8 @@
   double operator/(const Time &rhs) const;
   const Time operator%(int32_t rhs) const;
 
+  const Time operator-() const;
+
   bool operator==(const Time &rhs) const;
   bool operator!=(const Time &rhs) const;
   bool operator<(const Time &rhs) const;