0.1.50

• pdfkit updated to 0.9.0
• fontkit updated to 1.7.8
• Solved heavy use of memory
• Supported PNG with alpha channel
• Add encryption and access privileges, example of usage:

var docDefinition = {
	//userPassword: '123',
	ownerPassword: '123456',
	permissions: {
		printing: 'highResolution', //'lowResolution'
		modifying: false,
		copying: false,
		annotating: true,
		fillingForms: true,
		contentAccessibility: true,
		documentAssembly: true
	},
	content: [
		'...'
	]
};