We cannot allow restarting the server with a lower_case_table_names
setting which is different from the setting that was used when the
server was initialized, because the collations used by the DD tables
is defined at initialization time, while the server operates according
to the new l_c_t_n setting internally. Thus, this would lead to an
inconsistency in the way identifiers are compared and ordered.

This patch implements the following:

1. Abort server restart if the lower_case_table_names setting is
   different from the setting which was used during --initialize.

2. (Unrelated to this bug) When looking up the property key 'DD_VERSION'
   in the DD table 'dd_properties', if the key is not found, then also
   look for the key 'DD_version', which was used in DD version 1. The
   motivation for this is to provide a more meaningful error message.

3. (Unrelated to this bug) Add comments in sql/dd/dd_version.h
   describing the changes from DD version 1 to DD version 80004.

4. (Unrelated to this bug) Fix 'inheritance by domination' warnings.

Change-Id: I1cfae8cd7889edfe3adcee409dec9e83a1fd3881