Add some new video scripts and improve existing ones

dotfiles/bin/join-video

@@ -1,5 +1,7 @@
 #!/usr/bin/env bash
 
+# Re-encodes the video to get a more accurate timeline. If you want fast video joining at the expense of accuracy then use join-video-fast.
+
 if which tput >/dev/null 2>&1; then
     ncolors=$(tput colors)
 fi
@@ -35,7 +37,7 @@ output="${output_name}.mp4"
 
 printf "\n${YELLOW}${BOLD}Joining contents of '$filename'| output: $output${NORMAL}\n"
 
-ffmpeg -f concat -safe 0 -i "$filename" -c copy "$output"
+ffmpeg -f concat -safe 0 -accurate_seek -i "$filename.$extension" -c:v libx264 -c:a copy "$output"
 
 printf "\n${GREEN}${BOLD}Finished joining${NORMAL}\n\n"