Add I/O statements (fileReader and fileWriter)

This commit adds I/O statements to the deeply-embedded
streamit edsl. Also included in the examples directory
is the "file" example ported from the streamit source.
Add fir idealized
Put a sketch into fir_idealized
Add a note/stub in Core.hs about array dereference
Add a file with some example streamit bugs
minor: flag a couple things in comments
more small comments
more tweaks to bugs file
Change peeks type
Progress on array fusion layer but running into a typing problem
remove a bunch of Elt a, Elt b constraints
Remove more Elt constraints.  partial Fir_idealized prototype type checks
Add a array deref stub so I could move forward in Fir_idealized
sketch part of zipWith
Add a placeholder for fold and add a list of new head elements to the Stream type
Add a simple run_all bash script.
Merge branch 'master' of github.iu.edu:adkulkar/streamit-edsl
adding a cabal test-suite to test all examples
Several changes.

* Added support for arrays and array dereferences
* Rename incr and decr to .++ and .-- respectively
* Add an evaluator for expressions: Exp a -> a
* Added operators such as +=, *=, /=
* Simplified code generation
* Add a simple vec add example
Incremental progress on stream rep for functional layer.