filter out carriage returns for quasiquotes

There is a consistency problem when handling carriage returns across Shakespeare and Shelly.
In windows, 'st' returns \r\n but 'textFile' returns \n.

Shelly.readfile returns \r\n but Data.Text.IO.readFile retuns \n. I will add a pull request for Shelly as https://github.com/yesodweb/Shelly.hs/pull/44

(interpolated-string-perl6 'q' and 'qc' return \n only)

I think most consistent behavior is to just drop the '\r' across the board when reading and leave the writing the way it is. This is consistent with Data.Text.IO readFile writeFile.

https://gist.github.com/gbwey/6833805
from the above gist: this is what we have now:
*Test6> main
 120 13 10 121      :st
 120 10 121           :interpolated string perl6
 120 13 13 10 121  :Shelly.writefile st as abc then Shelly.readfile
 120 10 10 121      :T.readFile abc
 120 10 10 121      :textFile abc

 120 13 10 121      :Shelly.readfile ab
 120 10 121         :T.readFile ab
 120 10 121         :textFile ab

and after the changes for the two pull requests this is the result

*Test6> main
 120 10 121         :st
 120 10 121         :interpolated string perl6
 120 10 121         :Shelly.writefile st as abc then Shelly.readfile
 120 10 121         :T.readFile abc
 120 10 121         :textFile abc

 120 10 121         :Shelly.readfile ab
 120 10 121         :T.readFile ab
 120 10 121         :textFile ab

Thanks,
Grant