method on Iterable to replace null elements #190
test for #190
changing Iterable.defaultNullElements implementation to use a comprehension #190
Compile Iterable to js
Fix Iterable.skipping
fix failure messages
put Sequential, Empty, Sequence in a separate file
Iterable is now compiled from Ceylon
Compile Sequential, Sequence, Empty to js
improve failure messages
Improve String.equals to compare against [Character]
Sequential is now compiled
update language module for changes to string/character literal syntax
update tests for changes to string/character literal syntax
Merge branch 'master' of https://github.com/ceylon/ceylon.language into
infix

Conflicts:
	test/check.ceylon
	test/spans.ceylon
string rep of sequences changed
Fix #192: Range: Re-enable the optimized version of Range<Integer>.by()
(where we can use  a + instead of iterating doing ++) but using a native
helper method. This is a hack until we have reified generics and can write the
optimization in pure Ceylon.
Add a test for the lengthwise range op (start:length)
Util: Add a method for creating the Range (or empty) for a start:length SpreadOp
(for ceylon/ceylon-compiler#836)
Merge branch 'master' of https://github.com/ceylon/ceylon.language into infix