Merge 'DBIx-Class-current' into 'bulk_create'

r50744@cain (orig r3274):  castaway | 2007-05-09 22:42:11 +0000
No nested transactions in SQLite.

r50745@cain (orig r3275):  claco | 2007-05-10 00:18:35 +0000
resultset_class/result_class now (again) auto loads the specified class; requires Class::Accessor::Grouped 0.05000+

r50749@cain (orig r3279):  blblack | 2007-05-10 21:11:04 +0000
do not try to silently handle disconnects when in a manual txn_begin/txn_end transaction
r50750@cain (orig r3280):  blblack | 2007-05-10 21:13:14 +0000
docs about side-effects in txn_do coderef