THRIFT-2729: C++ - .clang-format created and applied

Client: C++
Patch: Konrad Grochowski

make style command added
diff --git a/compiler/cpp/src/main.h b/compiler/cpp/src/main.h
index 9b0f3f3..a4f81b3 100644
--- a/compiler/cpp/src/main.h
+++ b/compiler/cpp/src/main.h
@@ -29,9 +29,7 @@
  * Defined in the flex library
  */
 
-extern "C" {
-  int yylex(void);
-}
+extern "C" { int yylex(void); }
 
 int yyparse(void);
 
@@ -99,8 +97,8 @@
  * Flex utilities
  */
 
-extern int   yylineno;
-extern char  yytext[];
+extern int yylineno;
+extern char yytext[];
 extern FILE* yyin;
 
 #endif