Uncomment debug logging and compile it conditionally

c_src/sqlite3_drv.h

@@ -11,11 +11,10 @@
 #error "SQLite3 of version 3.6.1 minumum required"
 #endif
 
-
-
 // Path to file where data will be stored. 
 // It will be created if it doesn't exist
 #define DB_PATH "./store.db"
+#define LOG_PATH "/tmp/erlang-sqlite3-drv.log"
 
 // Binary commands between Erlang VM and Driver
 #define CMD_SQL_EXEC 2