Fail smime encryption for files bigger 1.5 GB

Since OpenSSL still has an issue encryption files
bigger 1.5 GB bphbu now fails the backup to let
the user know of the problem.

Relates to issue #305

Further Information:
openssl/openssl#1302

Author: sebastianfeldmann

src/Backup/Crypter/OpenSSL.php

@@ -100,6 +100,9 @@ public function crypt(Target $target, Result $result)
 
             $result->warn($name . ': The ' . $this->algorithm . ' algorithm is considered weak');
         }
+        if ($target->getSize() > 1610612736) {
+            throw new Exception('Backup to big to encrypt: OpenSSL SMIME can only encrypt files smaller 1.5GB.');
+        }
         parent::crypt($target, $result);
     }
 
@@ -121,7 +124,7 @@ public function simulate(Target $target, Result $result)
      * Is the configured cipher secure enough
      *
      * @return bool
-     * @throws \phpbu\App\Backup\Crypter\Exception
+     * @throws Exception
      */
     public function isUsingWeakAlgorithm(): bool
     {
@@ -170,8 +173,8 @@ public function getSuffix() : string
     /**
      * Decrypt the backup
      *
-     * @param  \phpbu\App\Backup\Target       $target
-     * @param  \phpbu\App\Backup\Restore\Plan $plan
+     * @param Target $target
+     * @param Plan $plan
      * @throws \phpbu\App\Exception
      */
     public function restore(Target $target, Plan $plan)
@@ -183,8 +186,8 @@ public function restore(Target $target, Plan $plan)
     /**
      * Create the Executable to run the 'mcrypt' command
      *
-     * @param  \phpbu\App\Backup\Target $target
-     * @return \phpbu\App\Cli\Executable
+     * @param Target $target
+     * @return Executable
      * @throws \phpbu\App\Exception
      */
     protected function createExecutable(Target $target) : Executable
@@ -195,8 +198,8 @@ protected function createExecutable(Target $target) : Executable
     /**
      * Create encryption OpenSSL
      *
-     * @param  \phpbu\App\Backup\Target $target
-     * @return \phpbu\App\Cli\Executable\OpenSSL
+     * @param Target $target
+     * @return Executable\OpenSSL
      * @throws \phpbu\App\Exception
      */
     private function createEncryptionOpenSSL(Target $target): Executable\OpenSSL
@@ -211,8 +214,8 @@ private function createEncryptionOpenSSL(Target $target): Executable\OpenSSL
     /**
      * Create decryption OpenSSL
      *
-     * @param  \phpbu\App\Backup\Target $target
-     * @return \phpbu\App\Cli\Executable\OpenSSL
+     * @param Target $target
+     * @return Executable\OpenSSL
      * @throws \phpbu\App\Exception
      */
     private function createDecryptionOpenSSL(Target $target): Executable\OpenSSL
@@ -227,8 +230,8 @@ private function createDecryptionOpenSSL(Target $target): Executable\OpenSSL
     /**
      * Setup an OpenSSL executable only thing missing is the decision of en or decryption
      *
-     * @param  \phpbu\App\Backup\Target $target
-     * @return \phpbu\App\Cli\Executable\OpenSSL
+     * @param Target $target
+     * @return Executable\OpenSSL
      * @throws \phpbu\App\Exception
      */
     private function createOpenSSL(Target $target): Executable\OpenSSL