Update podspec to 1.0.3

CocoaPods version + platform badge were showing "pod not found". Incrementing the version addresses this issue.

Author: george-lim

Envelope.podspec

@@ -1,7 +1,7 @@
 Pod::Spec.new do |spec|
 
   spec.name                  = "Envelope"
-  spec.version               = "1.0"
+  spec.version               = "1.0.3"
   spec.summary               = "OpenSSL-compatible file encryption in Swift"
 
   spec.description           = "Envelope is a hybrid cryptosystem that encrypts files efficiently and securely, supporting most symmetric and public-key ciphers. Envelope uses `AES256-CBC` and `RSA-2048` by default, and supports externally created (ie. OpenSSL) public-keys."