Standardized README headers

Previously, there were all capitalized headers and a few of them with
only the first letter capitalized.

We made this consistent with only the first letter capitalized and the
rest in lowercase.

README.md

@@ -18,19 +18,19 @@ RT and RTIR are commercially-supported software. To purchase support,
 training, custom development, or professional services, please get in
 touch with us at [[email protected]](mailto:[email protected]).
 
-## REQUIRED PACKAGES:
+## Required packages
 
 - RT version 4.4.1 or later.
 - Net::Whois::RIPE 1.31 is bundled with RTIR for compatibility with the
   API RTIR uses and for a fix to run without warnings under perl 5.18.
 
-## Upgrade instructions:
+## Upgrade instructions
 
 If you've installed a prior version of RTIR, you will need to follow
 special steps to upgrade.  See the docs/UPGRADING file for detailed
 information.
 
-## Installation instructions:
+## Installation instructions
 
 1. Install the current release of the RT 5.0 series following RT's
 regular installation instructions
@@ -94,7 +94,7 @@ Countermeasures queue.
 5. You can override values defined in RTIR_Config.pm by creating
    RTIR_SiteConfig.pm in /opt/rt5/etc/ and adding your customizations.
 
-## SETTING UP THE MAIL GATEWAY
+## Setting up the mail gateway
 
 An alias for the Incident Reports queue will need to be configured.
 Add the following lines to /etc/aliases (or your local equivalent):
@@ -145,7 +145,7 @@ You should substitute the URL for RT's web interface for http://rt.example.com/.
 - RTIR mailing list
    - Subscribe by sending mail to [[email protected]]([email protected]).
 
-## DEVELOPMENT
+## Development
 
 If you would like to run RTIR's tests, you need to set a few environment
 variables:
@@ -166,6 +166,6 @@ These are intended to be run before installing RTIR.
 Like RT, RTIR expects to be able to create a new database called rt5test
 on your system
 
-## REPORTING BUGS
+## Reporting bugs
 
 To report a bug, send email to [[email protected]](mailto:[email protected]).