Initial implementation of is default(42) on any hash/array
run new test file, ivanoff++
support for "is dynamic" and CALLER:: whining.
$_, $/ and $! are implicitly dynamic.
run S06-operator-overloading/semicolon.t, ivanoff++
Merge pull request #190 from timo/require_is_dynamic

Require "is dynamic"
add a typed exception

for accessing stuff through CALLER that is not dynamic
typed exceptions for if()
Rename exception class, jnthn++
remove Perl6::ConstantFolder

it was not really needed, and the optimizer does
constant folding much more generally
Add struct member for "is_dynamic" to be on the safe side
$/, $! and $/ are now default Nil and dynamic
No longer need to special case $/, $! and $_
Assigning Nil / undefine a scalar now also sets default for untyped scalars
Make select() more awesome and more useful.

Add a default block that runs when no other candidate is ready.

When more than one candidate is ready, pick one at random.
Make any container named ?*foo dynamic by default
No longer need to check name for OUTER:: access
Up the default thread pool maximum.
Fix a typo in the error message.

Ha-ha!
Make Nil assignment on hash/array elements with defaults just work