Update composer.json and .travis.yml as per #205

Author: ivanlanin

.travis.yml

@@ -18,8 +18,9 @@ before_script:
   ## Composer
   # - curl -s http://getcomposer.org/installer | php
   # - php composer.phar install --prefer-source
+  - composer self-update
+  - composer require dompdf/dompdf
   - composer install --prefer-source
-  - composer selfupdate --quiet
   ## PHP_CodeSniffer
   - pyrus install pear/PHP_CodeSniffer
   - phpenv rehash

composer.json

@@ -37,13 +37,13 @@
         "ext-zip": "*"
     },
     "require-dev": {
-        "phpunit/phpunit": "3.7.*",
-        "dompdf/dompdf" : "0.6.*"
+        "phpunit/phpunit": "3.7.*"
     },
     "suggest": {
-        "ext-gd2": "*",
-        "ext-xmlwriter": "*",
-        "ext-xsl": "*"
+        "ext-gd2": "Required to add images",
+        "ext-xmlwriter": "Required to write DOCX and ODT",
+        "ext-xsl": "Required to apply XSL style sheet to template part",
+        "dompdf/dompdf": "Required to write PDF"
     },
     "autoload": {
         "psr-4": {