README: added ceylon-common dependency
Fix minor typo in error report
Remove dead code
No longer error on circular dependencies between modules - #461
fix bug spotted by Tom
enhance test
fix #471
Merge remote-tracking branch 'upstream/sequential'
Declaration: cache the qualified name string
Declaration: made equals faster by adding fast cases and comparing the qualified name rather than the container
Package: cache the qualified name
ProducedType: cache the super type lookup
TypeDeclaration: made equals faster with fast case
Declaration.equals: reverted part of my equals optimisation becuse it was not correct
Fix invalid annotation example.

Now resembles the example found on the ceylon-lang.org introduction
page.
Added getNonemptySequentialType()
removed capture analysis from typechecker
Merge branch 'master' of github.com:ceylon/ceylon-spec
rename
allow shortcut refinement with => in interface bodies fixes #478