Bump deps, bump travis to 2.5

.travis.yml

@@ -12,6 +12,7 @@ rvm:
   - 2.3.3
   - 2.4.1
   - 2.4.2
+  - 2.5.0
   - ruby-head
 matrix:
   allow_failures:

squib.gemspec

@@ -29,16 +29,16 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(/^(spec|samples|docs|benchmarks)\//)
   spec.require_paths = ['lib']
 
-  spec.add_runtime_dependency 'cairo',                 '1.15.10'
+  spec.add_runtime_dependency 'cairo',                 '1.15.11'
   spec.add_runtime_dependency 'classy_hash',           '0.2.1'
-  spec.add_runtime_dependency 'gio2',                  '3.1.8'
-  spec.add_runtime_dependency 'gobject-introspection', '3.1.8'
-  spec.add_runtime_dependency 'highline',              '1.7.8'
+  spec.add_runtime_dependency 'gio2',                  '3.2.1'
+  spec.add_runtime_dependency 'gobject-introspection', '3.2.1'
+  spec.add_runtime_dependency 'highline',              '1.7.10'
   spec.add_runtime_dependency 'mercenary',             '0.3.6'
-  spec.add_runtime_dependency 'nokogiri',              '1.8.1'
-  spec.add_runtime_dependency 'pango',                 '3.1.8'
+  spec.add_runtime_dependency 'nokogiri',              '1.8.2'
+  spec.add_runtime_dependency 'pango',                 '3.2.1'
   spec.add_runtime_dependency 'roo',                   '2.7.1'
-  spec.add_runtime_dependency 'rsvg2',                 '3.1.8'
+  spec.add_runtime_dependency 'rsvg2',                 '3.2.1'
   spec.add_runtime_dependency 'ruby-progressbar',      '1.9.0'
 
   spec.add_development_dependency 'bundler'