MD026 Trailing punctuation in header

This rule is broken when we have ".,;::!?" in the headers.
We have removed the ones with ":" but kept the ones
with "?", so this rule will always warn in these cases.

docs/en/installation/deploying-on-heroku.md

@@ -127,7 +127,7 @@ Add this to `config/secrets.yml`, under the `production:` section:
 
 Important: Turn on one worker dyno so that emails get sent.
 
-## Optional but recommended:
+## Optional but recommended
 
 ### Install rails\_12factor and specify the Ruby version
 

docs/en/installation/servers.md

@@ -1,8 +1,8 @@
 # Production and Staging servers
 
-## Recommended Minimum System Requirements:
+## Recommended Minimum System Requirements
 
-### 1. Production Server:
+### 1. Production Server
 
 - Distribution: Ubuntu 16.04.X
 - RAM: 32GB
@@ -10,7 +10,7 @@
 - Hard Drive: 20 GB
 - Database: Postgres
 
-### 2. Staging Server:
+### 2. Staging Server
 
 - Distribution: Ubuntu 16.04.X
 - RAM: 16GB