Improve description of service levels

Issue

• Unclear difference in Support Levels
• When creating a new case engineers will have to select the Support Level. Only after referring to https://access.redhat.com/support/offerings/production/sla.html it became clear to me what the difference is.
• This link is not simply available to engineers logging a case.
• To simplify the choice for engineers and to reduce wrong picks I suggest to change the items in the pull-down menu to:

Premium  (24x7 for Severity 1 and 2)
Standard (Business hours only)

• I also would like to suggest to include the SLA link under the "Support Level"-label.
• When my customer's engineers open a support case through the portal, they are asked to select a support level without being provided with context as to what these levels signify.
• We would like a brief parenthetical remark for each option. "Premium (24x7 for Severity 1 and 2)" rather than just "Premium", and "Standard (Business hours only)" rather than just "Standard".
• We would also like a link to https://access.redhat.com/support/offerings/production/sla.html for the SLA definition.