Crash on force unwrap of corners

[cmtrounce]

In 'draw' function of RSCornersLayer.swift,

let dict = corners[idx] as! NSDictionary force cast causing a crash.

When scanning a barcode, this causes a hard crash.

[akuehlewind]

Got the same error RSCornersLayer.swift -> 41

To fix it replace:

let dict = corners[idx] as! NSDictionary
                
                let x = CGFloat((dict.object(forKey: "X") as! NSNumber).floatValue)
                let y = CGFloat((dict.object(forKey: "Y") as! NSNumber).floatValue)
                if i == 0 {
                    ctx.move(to: CGPoint(x: x, y: y))
                } else {
                    ctx.addLine(to: CGPoint(x: x, y: y))
                }

with:

let point = corners[idx] as! CGPoint                
                if i == 0 {
                    ctx.move(to: point)
                } else {
                    ctx.addLine(to: point)
                }

[lotfyahmed]

Please create new branch (or fork) to fix it with the above solution.

[lotfyahmed]

@akuehlewind Please create pull request to merge it on the master

And how to install this solution from Cocoa pod?

The current profile has:

pod 'RSBarcodes_Swift', :git => 'git@github.com:yeahdongcn/RSBarcodes_Swift.git', :branch => 'master'

Thanks

[lotfyahmed]

@yeahdongcn Please accept the pull request to fix this crash if it is a correct solution.