Changed mysql-test to print warnings for not existing table to DROP TABLE

Cleaned up test; Removed wrong DROP TABLE commands and use standard table and database names.
changed store_warning() -> push_warning_print()

mysql-test/t/join.test

@@ -1,7 +1,9 @@
 #
 # This failed for lia Perminov
 #
+--disable_warnings
 drop table if exists t1,t2,t3;
+--enable_warnings
 
 create table t1 (id int primary key);
 create table t2 (id int);