begin attempt to disable widgets when not applicable
rename reactive object network() to network1() to avoid name conflicts with network function
to disable aftersymm radio buttons, not functional yet
change warnings when color coding with more than 9 levels to be yellow alert boxes from shinyBS package
can disable selectInput menu (or anything else whose html has the disabled property). radio buttons do not have this, simply color them gray when not applicable
Merge branch 'disable'

Conflicts:
	server.R
disable selection of degree type
add ability for widgets to be enabled again after disabling. completes fix of issue #19