fix bug for "catch" command (#26)

Author: Naoto Ono

lib/debug/breakpoint.rb

@@ -209,7 +209,7 @@ def setup
       @tp = TracePoint.new(:raise){|tp|
         exc = tp.raised_exception
         exc.class.ancestors.each{|cls|
-          suspend if pat === cls.name
+          suspend if @pat === cls.name
         }
       }
     end

lib/debug/session.rb

@@ -852,7 +852,7 @@ def break? file, line
 
     def add_catch_breakpoint arg
       bp = CatchBreakpoint.new(arg)
-      add_braekpoint bp
+      add_breakpoint bp
     end
 
     def add_check_breakpoint expr