Updated readme for text generation

https://github.com/markevans/dragonfly/issues/272#issuecomment-16857546
Merge pull request #273 from elfassy/patch-2

Updated readme for text generation
Job#fetch_url escapes URL first to allow for non-english characters in URLs.
Merge pull request #278 from ismasan/fetch_non_english_url

Job#fetch_url supports URLs with non-english characters
Sometimes ActionDispatch::Cookies isn't there. middleware stack is completely impossible to conditionally insert (as far as I can tell) so just be pragmatic and insert it in approximately the right place
support fog's new use_iam_profile option
small error in error message - would have blown up before forming message
Use rbconfig to detect Windows OS
need require tempfile in spec helper
Using "get_bucket" seems inefficient as it will return a list of all of the objects in the bucket. Using "get_bucket_location" seems better as it will return just the location information of buckets that exist.
Job::Step#to_a (no change in functionality)
Allow passing a pathname to fetch_file
fixed identify regexp
jobs' url_attributes shouldn't interfere with one another
pdfs do not return true for image? analyser
no need for analyse option in validates_property
Merge branch 'master' into refactor

Conflicts:
	extra_docs/ImageMagick.md
	lib/dragonfly/data_storage/s3data_store.rb
	lib/dragonfly/image_magick/utils.rb
	lib/dragonfly/job.rb
	spec/dragonfly/job_spec.rb
	spec/spec_helper.rb