Small screen issue list fixes

Created by: jogwen

Replaces https://github.com/aptivate/econsensus/pull/60 which got closed inadvertently. This one:

• is tidier (without extra merged commits)
• includes the 'Last Modified' label fix for Proposal list screen
• also includes new fix to implement Jay's suggestion of removing "Excerpt" label entirely and allow excerpt value to span entire width.