docs: improve grammar and fix typos (#5361)

This alters some comments in source files, but is interested mainly in documentation files and help messages.

cmd/lsf/lsf.go

@@ -93,13 +93,13 @@ can be returned as an empty string if it isn't available on the object
 the object and "UNSUPPORTED" if that object does not support that hash
 type.
 
-For example to emulate the md5sum command you can use
+For example, to emulate the md5sum command you can use
 
     rclone lsf -R --hash MD5 --format hp --separator "  " --files-only .
 
 Eg
 
-    $ rclone lsf -R --hash MD5 --format hp --separator "  " --files-only swift:bucket 
+    $ rclone lsf -R --hash MD5 --format hp --separator "  " --files-only swift:bucket
     7908e352297f0f530b84a756f188baa3  bevajer5jef
     cd65ac234e6fea5925974a51cdd865cc  canole
     03b5341b4f234b9d984d03ad076bae91  diwogej7
@@ -134,7 +134,7 @@ Eg
 Note that the --absolute parameter is useful for making lists of files
 to pass to an rclone copy with the --files-from-raw flag.
 
-For example to find all the files modified within one day and copy
+For example, to find all the files modified within one day and copy
 those only (without traversing the whole directory structure):
 
     rclone lsf --absolute --files-only --max-age 1d /path/to/local > new_files