Remove unrequired default decls.

We ignored these before; now we pay attention to them, and hit a
bootstrap issue.
First pass at getting variable traits in place.
Implement default trait on variables.

Again, a first pass, but seems to basically work.
Add "is readonly" and "is rw" traits on variables
Add stubs for "is dynamic" and "is context", so at least they don't bomb like before
Add "is TypeObject" and "of TypeObject" traits
Some code cosmetics and comments in variable traits
Stub phaser traits: alas, dispatch is not yet successful
Make variable "is" trait a stub again, it is not the same as "of"
"is context" is old for "is dynamic", so we don't need it
Make "will phaser {]' parameter mandatory
Make sure we decont the "of" so that it works, suggested by jnthn++
Added additional dereference, as suggested by jnthn++

It doesn't break anything new, and makes some other errors messags more sane.
Correct signature for "will phaser {}" dispatches, suggested by jnthn++
First sort of functional phasers implementation with "will" variable trait
Add provisional "will start" state variable trait
Make "my $a will foo" die with a more awesome error message
Temporary more/less LTA error message for 'my $a will foo'
Make variable trait "is TypeObject" fail with a better message for now
Merge branch 'var-traits' into nom

Variable traits such as "is default" and "will leave {}" now work (mostly)