Updated _directories.erb to add support for 'SetEnv'

Updated _directories.erb to add support for 'SetEnv'.
MODULES-1403 - fix doc bug
MODULES-1384 - idempotency for wsgi_script_aliases

When parsing wsgi_aliases, sort the keys then generate the underlying template.
Merge pull request #936 from mhaskel/MODULES-1384

MODULES-1384 - idempotency for wsgi_script_aliases
Merge pull request #935 from mhaskel/MODULES-1403

MODULES-1403 - fix doc bug
Add configurable options for mpm_event
Add basic mpm_event docs, fix formatting, appease older ruby
Merge pull request #934 from muresan/patch-1

Updated _directories.erb to add support for 'SetEnv'
Merge pull request #939 from stumped2/feature/master/mpm_event

Add configurable options for mpm_event
Add metadata summary per FM-1523
Fix MODULES-1510

Removes wiki link from Contributing section and replaces it with newly-created docs site link.
Merge pull request #942 from laurenrother/summary

Add metadata summary per FM-1523
Add support for mod_auth_cas module configuration