ELAN basic edit

[letuananh]

• Create a blank EAF file
• Update author
• Update created date
• Update media file (media_file, media_url, relative_media_url)
• Create new annotations
• Update annotation values
• Create new tiers
• Change tier names
• Edit controlled vocabulary (CV)
• Create new CV entries
• Edit CV entries
• Edit Timeslot values
• Shift timeline (i.e. batch edit timeslots)
• Remove annotations (Related: Support removing annotations #22)
• Remove tiers
• Remove CV entries (unused only)