Calibre 2.44 发布电子书管理软件

Calibre 2.44 发布，此版本更新内容如下：

Allow setting the cover for a book from one of the book’s formats by right clicking on the format in the Book details panel.
Closes tickets: 1515411
Allow drag and drop of all file types onto the book details panel and the format list in the edit metadata dialog.
Closes tickets: 1515407
Edit Book: When inserting an image into the current document, add a button to paste the image from the clipboard
Edit Book: Change the suggested prefix for bulk renaming of files depending on the type of files being renamed.
Closes tickets: 1514468
On Linux, use the system tray icon from the system theme, if available

Fix for error when connecting to some Android phones/tablets that have an SD card on OS X and Linux
Linux build: Fix problem with pointing hand mouse cursor not using the system theme on some Linux systems
Fix the device view state not being saved when a connected device is ejected/disconnected
Edit Book: Fix saving fails if the original file is deleted during editing session
Closes tickets:1513849
E-book viewer: When doing a search do not match text in comments, attributes and inappropriate tags, such as <script> and <style>