CLI: change "-suppress warnings" option to "-nowarn"

Following the rule of the least surprise: this option is named "-nowarn" in
other JVM language compilers. Besides, having an option with an argument which
can take exactly one predefined value is sort of confusing

compiler/tests/org/jetbrains/jet/cli/CliCommonTest.java

@@ -52,12 +52,7 @@ public class CliCommonTest extends CliBaseTest {
     }
 
     @Test
-    public void suppressAllWarningsLowercase() throws Exception {
-        executeCompilerCompareOutputJVM();
-    }
-
-    @Test
-    public void suppressAllWarningsMixedCase() throws Exception {
+    public void suppressAllWarningsJvm() throws Exception {
         executeCompilerCompareOutputJVM();
     }
 

compiler/tests/org/jetbrains/jet/cli/KotlincExecutableTestGenerated.java

@@ -89,14 +89,9 @@ public class KotlincExecutableTestGenerated extends AbstractKotlincExecutableTes
             doJvmTest("compiler/testData/cli/jvm/simple.args");
         }
         
-        @TestMetadata("suppressAllWarningsLowercase.args")
-        public void testSuppressAllWarningsLowercase() throws Exception {
-            doJvmTest("compiler/testData/cli/jvm/suppressAllWarningsLowercase.args");
-        }
-        
-        @TestMetadata("suppressAllWarningsMixedCase.args")
-        public void testSuppressAllWarningsMixedCase() throws Exception {
-            doJvmTest("compiler/testData/cli/jvm/suppressAllWarningsMixedCase.args");
+        @TestMetadata("suppressAllWarningsJvm.args")
+        public void testSuppressAllWarningsJvm() throws Exception {
+            doJvmTest("compiler/testData/cli/jvm/suppressAllWarningsJvm.args");
         }
         
         @TestMetadata("wrongAbiVersion.args")

compiler/tests/org/jetbrains/jet/codegen/forTestCompile/ForTestCompileRuntime.java

@@ -91,7 +91,7 @@ public class ForTestCompileRuntime {
                 "-d", destDir.getPath(),
                 "-no-stdlib",
                 "-no-jdk-annotations",
-                "-suppress", "warnings",
+                "-nowarn",
                 "-annotations", JetTestUtils.getJdkAnnotationsJar().getAbsolutePath(),
                 "-classpath", classPath
         );