Remove cucumber monkey patch translating steps:

It was initially added to allow reuse of aruba cucumber steps, using
`must' instead of `should'. This is creating more harm than good, hence
we remove it and implements all missing steps, using aruba API.

features/steps/output_steps.rb

@@ -0,0 +1,23 @@
+Then /^the output must match \/([^\/]+)\/$/ do |pattern|
+  assert_matching_output pattern, all_output
+end
+
+Then /^the output must contain "([^"]+)"$/ do |content|
+  assert_partial_output content, all_output
+end
+
+Then /^the output must contain:$/ do |content|
+  assert_partial_output content, all_output
+end
+
+Then /^the output must not contain "([^"]+)"$/ do |content|
+  assert_no_partial_output content, all_output
+end
+
+Then /^the output must contain exactly "([^"]+)"$/ do |content|
+  assert_exact_output content, all_output
+end
+
+Then /^the output must contain exactly:$/ do |content|
+  assert_exact_output content, all_output
+end