BigDecimal#div should raise FloatDomainError if NaN is involved in 1.9
BigDecimal#div should return 0 if divided by Infinity and no precision given in 1.9
BigDecimal#div should raise ZeroDivisionError if divided by zero and no precision given in 1.9
VERSION toplevel constant is not defined in 1.9 or 2.0. Fixes #665
Do not attempt to reuse SSL session.

JRuby does not yet implement OpenSSL::SSL::Session, so the reuse
of session broke net/http in JRuby's Ruby 2.0 mode. Since it's
only to speed up the establishment of SSL connections, we can
comment it out until we support OpenSSL::SSL:Session.

Related: #197.
BigDecimal#div should raise FloatDomainError if (+|-) Infinity divided by 1 and no precision given
Add Kernel#__dir__. Fixes #651.
Merge pull request #669 from atambo/bigdecimal_div_nan

Fix BigDecimal#div rubyspecs