Unify the way to set compiler options using System.properties

Now compiler flags with boolean values which are controlled by system
properties could be set in similar way. The following syntax is
appropriate. For setting flag:
'-DflagName,'-DflagName=[y|Y|true|TRUE|yes|YES|on|ON]'
for unsetting flag:
'-DflagName=[n|N|false|FALSE|no|NO|off|OFF]'

build-common/src/org/jetbrains/kotlin/incremental/storage/externalizers.kt

@@ -57,12 +57,12 @@ object LookupSymbolKeyDescriptor : KeyDescriptor<LookupSymbolKey> {
     override fun save(output: DataOutput, value: LookupSymbolKey) {
         if (storeFullFqName) {
             output.writeByte(0)
-            output.writeUTF(value.name)
-            output.writeUTF(value.scope)
-        } else {
-            output.writeByte(1)
             output.writeInt(value.nameHash)
             output.writeInt(value.scopeHash)
+        } else {
+            output.writeByte(1)
+            output.writeUTF(value.name)
+            output.writeUTF(value.scope)
         }
     }