Fix #1745: Rename Progress bar images in HUD theme

This is a partial fix that should resolve #1745.

-- It removes an extra "-bar" from the progress bar images in the HUD theme.
-- It removes an older "-bar-regular" from file names to match the file names in the regular theme
-- It corrects a misspelled "indeterminate" in the progress indicator
Merge pull request #1786 from ahankinson/fix-issue1745

Fix #1745: Rename Progress bar images in HUD theme