Added single key assignment to Merb.config
Added single key assignment to Merb.config

Example:
Merb.config.beer # => "good"
Merb.config.beer = "Awesome"
Merb.config.beer # => "Awesome"

wycats/merb,wycats/merb,wycats/merb,wycats/merb,benburkert/merb-core,merb/merb,merb/merb,wycats/merb,benburkert/merb-core,merb/merb