Added driver to support dotConnect for MySql
Code cleanup
Fix NH-2463 and NH-2688 by removing unnecessary casts to the same type of to superclass (upcast) in expressions of type Convert, ConvertChecked and TypeAs
Fix typo in last commit
Optimize access to dictionaries across all code.
Added new SqlTokenizer class to support parsing of non-trivial SELECT statements. Modified SqlString.Parse() to ignore parameter references in SQL comments.
NH-2977

- Added limit SQL generation for SQL Server queries with comments, common table expressions, and stored procedure invocations.
- Modified loader to fall back to client-side limit/offset behavior if dialect does not support generation of server side limit/offset SQL for a given (custom) SQL statement.
Paging for MsSql2012 changed to the new recommended standard syntax and made MsSql20xxDialect.GetLimitString() implementations more consistent.
Bug fixes in SQL Tokenizer.
Fix NH-3138 caused by MsSqlSelectParser
Add test for csharper2010's note at #117
Move NHibernate.Hql.Ast.ANTLR.Loader.QueryLoader to NHibernate.Loader.Hql namespace to match Hibernate
Fix for NH-3280
Add Ingres v9+ Dialect

Supporting paging on Ingres DB v9+
Make tests for NH-2736 applicable only to dialects which support variable limits
Minor change to NH-3280 test case to make it green with Firebird dialect.
Another attempt to fix NH-3280 for Firebird dialect.
Spelling in comments.
Remove the only NHibernate use of ImmutableSet, to prepare for .Net 4 which doesn't have this type of set. It was only class private anyway.
Make IPersistentCollection.GetSnapshot() return object instead of ICollection. Some of the implementations return sets, and when those are BCL sets they don't implement non-generic ICollection. Since the contents of the snapshots are never accessed outside each type of persistent collection (and probably never should be), we might as well make it a completely opaque object.