Caching Shelf manifest.

This is part of a fix for issue #582: provided the shelf manifest has been downloaded at least once, this will prevent the shelf being blank when there's no network connection.
Network Connection Alert

Will only display warning message if the JSON Issues List can't be downloaded and there is no cached version.  Customizable message via localized strings.  Partial fix for Issue #582
Fixed whitespaces and naming convention.
Raised deployment target in Baker target to iOS 5.0 and set the default deployment family to 'iPad'
Fixed Baker orientation recognition problems (switched form old orientation variable to new book.orientation params)
Resume for pending Newsstand downloads.

This adds support for resuming incomplete Newsstand downloads.
Partial fix for #593.
Merge branch 'master' of github.com:Simbul/baker
Added "connecting" before "downloading" issue.

In a Newsstand-enabled shelf, tapping the "download" button will show a "connecting…" message before the "downloading…" message.
This will hopefully make it clear that - when a network connection is missing - download has not started yet, and that it will be started automatically by Newsstand as soon as a connection is available.

Closes #593
Fixed page reloading when closing a modal webview
Merge branch 'master' of github.com:Simbul/baker
Restored double tap on index view to close it.

Fixes #588.
Readme for 4.0
Removed stray file reference.
Fixes #608.
Added paging check.
Merge pull request #620 from danielreiser/master

Enable paging of webView with meta-tag
Added colored placeholder for cover image, closes #581
Added current status to issue UI for debugging
Helper method to get product IDs in IssuesManager
Added productID and price to BakerIssue
Added status 'purchasable' for BakerIssue