Add 'Fit to window' action

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The plugin is so efficient! However, I hope it can add more page magnification in the future version! For example:

• Fit to Window
• Fit Full Page to Window
• Show Section Title and Directory
• Zoom Value

Especially the first one, it is very convenient when reading PDF files. In fact, I hope some basic function of Browser PDF viewer could be added. And the Acrobat spoils me.The Link of Acrobat Besides, the funciton Find in Document is expedient! Thank you so much!