Update to newer versions of dependencies

Important:
The scriptotek/marc library was updated to version 2.0
If you work with MARC records, please see the changelog
of that library as there are breaking changes there:

https://github.com/scriptotek/php-marc/blob/master/CHANGELOG.md#200---2018-10-23

Author: danmichaelo

CHANGELOG.md

@@ -10,6 +10,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 - Add portfolios and representations to Bib objects.
 
+### Changed
+
+- Updated [scriptotek/marc](https://github.com/scriptotek/php-marc/) to version 2.0.
+  Please see [the corresponding CHANGELOG](https://github.com/scriptotek/php-marc/blob/master/CHANGELOG.md#200---2018-10-23) for information about changes that might break your app if you work with MARC records.
+
 ### Fixed
 
 - Set MMS id on Bib object when initiated from SRU response.

composer.json

@@ -9,25 +9,24 @@
     "require": {
         "php" : ">=5.6",
         "ext-json": "*",
-        "scriptotek/marc": "^1.0 || dev-master",
+        "scriptotek/marc": "^2.0 || dev-master",
         "danmichaelo/quitesimplexmlelement": "^1.0",
         "scriptotek/sru-client": "^0.6",
         "psr/http-message": "^1.0",
         "php-http/client-implementation": "^1.0",
-        "php-http/httplug": "^1.1",
+        "php-http/httplug": "^1.1 || ^2.0",
         "php-http/message-factory": "^1.0",
         "php-http/discovery": "^1.0",
         "php-http/client-common": "^1.5"
     },
     "require-dev": {
-        "phpspec/phpspec": "^3.4",
-        "bossa/phpspec2-expect": "^2.1",
-        "leanphp/phpspec-code-coverage": "~3.1",
+        "phpspec/phpspec": "^3.4 || ^4.0 || ^5.0",
+        "bossa/phpspec2-expect": "^2.1 || ^3.0",
         "wp-cli/php-cli-tools": "^0.11.1",
         "php-http/mock-client": "^1.0",
         "php-http/message": "^1.0",
         "guzzlehttp/psr7": "^1.0",
-        "php-http/guzzle6-adapter": "^1.1",
+        "php-http/guzzle6-adapter": "^1.1 || ^2.0",
         "squizlabs/php_codesniffer": "^3.3"
     },
     "license": "MIT",