Add a few lines describing the merb submodules

A complete list is available
http://rubydoc.info/github/merb/merb/master/frames

Merb consists of the following parts:

merb-core: Core functionality needed to bootstrap and run an application.
merb-action-args: Plugin to handle request parameters as parameters to controller actions.
merb-assets: Asset handling.
merb-slices: Slices are merb's application modules.
merb-cache: Support for content caches, e.g., memcache.
merb-gen: Generators for applications, plugins, and components.
merb-haml: Support for HAML
merb-helpers: Helpers for text and HTML formatting.
merb-mailer: MVC mail sending from an application.
merb-param-protection: Filter request parameters in controllers and logs.
merb-exceptions: Exception notifications as mail and through web hooks.

Requested by:	erwin

www/rubygem-merb-assets/pkg-descr

@@ -1,3 +1,4 @@
 Merb is a web development framework for fast, simple, and powerful development.
+merb-assets provides supports for asset handling.
 
 WWW: http://www.merbivore.com/

www/rubygem-merb-core/pkg-descr

@@ -1,3 +1,4 @@
 Merb is a web development framework for fast, simple, and powerful development.
+merb-core provides core functionality needed to bootstrap and run an application.
 
 WWW: http://www.merbivore.com/

www/rubygem-merb-haml/pkg-descr

@@ -1,3 +1,4 @@
 Merb is a web development framework for fast, simple, and powerful development.
+merb-haml provides support for HAML
 
 WWW: http://www.merbivore.com/

www/rubygem-merb-helpers/pkg-descr

@@ -1,3 +1,4 @@
 Merb is a web development framework for fast, simple, and powerful development.
+merb-helpers provides helpers for text and HTML formatting.
 
 WWW: http://www.merbivore.com/

www/rubygem-merb-param-protection/pkg-descr

@@ -1,3 +1,4 @@
 Merb is a web development framework for fast, simple, and powerful development.
+merb-param-protection allows filtering request parameters in controllers and logs.
 
 WWW: http://www.merbivore.com/