Classes:
- LINQ::DBI
- LINQ::LibXML

Optimization:
- select_many: avoid to_list
- sequence_equal: avoid to_list
- any: short-circuit true, avoid to_list
- all: short-circuit false, avoid to_list
- contains: short-circuit true, avoid to_list

Features:
- LINQ::Collection->to_array ought to return a tied array pointing back to the collection
