allow multi-angle pod formatcodes, forbid nesting in C< and V<
allow nested FCodes, forbid nesting in C<> and V<>
lots of debugging output
lots of reworking of the grammar.
allow output blocks for preformatted text.
start to implement :allow.
Make $!, $/ and $_ default Nil
Slight optimization in .join, as suggested by jnthn++

Doesn't make "say $*VM" much faster, need more in the range of 10000 elements
to join before it becomes noticeable.  And then only about 5%.
Provide basic threads and promises on JVM.

This builds upon the interop primitives and threading example by
sorear++ to provide a minimal Thread class, along with a thread pool
on which code can be scheduled to run. This in turn is used for a
basic implementation of promises/futures, with an async sub that
takes a code block and returns a Promise.
only dedent newlines found in the textual code of heredocs
always do the dedenting at compile-time
Special case 1 ** !NaN.

If someone knows how to make this more efficient, it might be a good idea.
Make sure Parcel.new actually works
pod_balanced_braces needs string merging for twines to work correctly.
nicer (and actually working) balanced-braces-combining.
format C, L, D and R format codes; hide extradata of D, L and X.
return the $text in any case.
Merge branch 'heredoc_trim_fix' of https://github.com/timo/rakudo into nom
Merge branch 'pod6-improvements' of https://github.com/timo/rakudo into nom
Add 'then' method to Promise.

Attaches a piece of work to do when the promise is fulfilled or
broken. Returns a new Promise that represents the completion of
this extra work, allowing chaining.