Bug fixes and minor functionality updates

Changes

• Fixed: When user sets minutes then manually sets hours to 24 hours minutes is not set to 0 as expected. #7
• Resolve all uses of deprecated code
• Added update handler to catch indirect modifications to bound field (e.g. if field is modified by a web resources the control will detect the change and update)
• Add aria labels to buttons
• Change label text from HRS to HR

PCF Controls

• Duration Picker - A react based duration picker that allows users to enter hours and minutes manually, by clicking the chevrons or manually entering time up to 24 hours.