Use single quotes to quote string literals

Double quotes are allowed in MySQL by default, but not if ANSI_QUOTES are on.

See: http://dev.mysql.com/doc/refman/5.0/en/string-literals.html
Merge pull request #324 from Symplicity/ansi_quotes

Use single quotes to quote string literals
MysqlAdapter::renameColumn keep column default

When renaming a column with a default value the default is removed after the rename, this proposal fixes that.
Merge pull request #325 from Alexssssss/patch-1

MysqlAdapter::renameColumn keep column default
psr-2
auto timestamp migration class names if auto_timestamp_class is set in configuration
Merge branch 'dev-master'