Updated Readme.

Author: aksh1t

README.md

@@ -245,11 +245,17 @@ adb push /path/to/your/document.pdf /sdcard/document.pdf
 ```diff
 # Uncomment this line to define a global platform for your project
 -   # platform :ios, '9.0'
-+   platform :ios, '11.0'
++   platform :ios, '12.0'
 ...
+```
+Add the podspec link for `PSPDFKit` in `ios/Podfile` as shown below:
+
+__Optional:__ If you wish to use a specific version of `PSPDFKit` or the nightly version, you should use the appropriate podspec link.
+
+```
 target 'Runner' do
   use_frameworks!
-+   pod 'PSPDFKit', podspec:'https://customers.pspdfkit.com/cocoapods/YOUR_COCOAPODS_KEY_GOES_HERE/pspdfkit/latest.podspec'
++   pod 'PSPDFKit', podspec:'https://customers.pspdfkit.com/pspdfkit-ios/latest-framework.podspec'
 ...
 end  
 ``` 

example/README.md

@@ -15,12 +15,12 @@ pspdfkit.password=YOUR_PASSWORD_GOES_HERE
 flutter.buildMode=debug
 ```
 
-3. Replace `YOUR_COCOAPODS_KEY_GOES_HERE` with your Cocoapods key in `pspdfkit-flutter/example/iOS/Podfile`
+3. __Optional:__ Replace the podspec link in `pspdfkit-flutter/example/iOS/Podfile` if you wish to use a specific version of `PSPDFKit`, or the nightly version.
 
 ```bash
 ...
 target 'Runner' do
-  pod 'PSPDFKit', podspec:'https://customers.pspdfkit.com/cocoapods/YOUR_COCOAPODS_KEY_GOES_HERE/pspdfkit/latest.podspec'
+  pod 'PSPDFKit', podspec:'https://customers.pspdfkit.com/pspdfkit-ios/latest-framework.podspec'
 ...  
 ```