src: add CHECK_{GE,GT,LE,LT} macros

Conform to the Google styleguide more and make cpplint happy, add more
CHECK macros.

Preemptively addresses cpplint's readability/check warnings ("Consider
using CHECK_GT instead of CHECK(a > b)".)

src/util.h

@@ -55,6 +55,10 @@ namespace node {
 #endif
 
 #define CHECK_EQ(a, b) CHECK((a) == (b))
+#define CHECK_GE(a, b) CHECK((a) >= (b))
+#define CHECK_GT(a, b) CHECK((a) > (b))
+#define CHECK_LE(a, b) CHECK((a) <= (b))
+#define CHECK_LT(a, b) CHECK((a) < (b))
 #define CHECK_NE(a, b) CHECK((a) != (b))
 
 #define UNREACHABLE() abort()