Clean up mount.go and vfs/help.go docs

* Title cleanups
* Typos
* `rclone mount vs rclone sync/copy` update with `File Caching`

cmd/mountlib/mount.go

@@ -86,7 +86,7 @@ When that happens, it is the user's responsibility to stop the mount manually wi
     # OS X
     umount /path/to/local/mount
 
-### Installing on Windows ###
+### Installing on Windows
 
 To run rclone ` + commandName + ` on Windows, you will need to
 download and install [WinFsp](http://www.secfs.net/winfsp/).
@@ -99,7 +99,7 @@ uses combination with
 packages are by Bill Zissimopoulos who was very helpful during the
 implementation of rclone ` + commandName + ` for Windows.
 
-#### Windows caveats ####
+#### Windows caveats
 
 Note that drives created as Administrator are not visible by other
 accounts (including the account that was elevated as
@@ -114,9 +114,9 @@ account (using [the WinFsp.Launcher
 infrastructure](https://github.com/billziss-gh/winfsp/wiki/WinFsp-Service-Architecture))
 which creates drives accessible for everyone on the system.
 
-### Limitations ###
+### Limitations
 
-This can only write files seqentially, it can only seek when reading.
+This can only write files sequentially, it can only seek when reading.
 This means that many applications won't work with their files on an
 rclone mount.
 
@@ -130,24 +130,24 @@ the directory cache.
 
 Only supported on Linux, FreeBSD, OS X and Windows at the moment.
 
-### rclone ` + commandName + ` vs rclone sync/copy ##
+### rclone ` + commandName + ` vs rclone sync/copy
 
 File systems expect things to be 100% reliable, whereas cloud storage
 systems are a long way from 100% reliable. The rclone sync/copy
 commands cope with this with lots of retries.  However rclone ` + commandName + `
 can't use retries in the same way without making local copies of the
-uploads.  This might happen in the future, but for the moment rclone
-` + commandName + ` won't do that, so will be less reliable than the rclone command.
+uploads. Look at the **EXPERIMENTAL** [file caching](#file-caching)
+for solutions to make ` + commandName + ` mount more reliable.
 
-### Filters ###
+### Filters
 
 Note that all the rclone filters can be used to select a subset of the
 files to be visible in the mount.
 
-### systemd ###
+### systemd
 
 When running rclone ` + commandName + ` as a systemd service, it is possible
-to use Type=notify. In this case the service will enter the started state 
+to use Type=notify. In this case the service will enter the started state
 after the mountpoint has been successfully set up.
 Units having the rclone ` + commandName + ` service specified as a requirement
 will see all files and folders immediately in this mode.

vfs/help.go

@@ -3,7 +3,7 @@ package vfs
 // Help contains text describing file and directory caching to add to
 // the command help.
 var Help = `
-### Directory Cache ###
+### Directory Cache
 
 Using the ` + "`--dir-cache-time`" + ` flag, you can set how long a
 directory should be considered up to date and not refreshed from the
@@ -18,12 +18,12 @@ like this:
 
     kill -SIGHUP $(pidof rclone)
 
-### File Caching ###
+### File Caching
 
 **NB** File caching is **EXPERIMENTAL** - use with care!
 
 These flags control the VFS file caching options.  The VFS layer is
-used by rclone mount to make a cloud storage systm work more like a
+used by rclone mount to make a cloud storage system work more like a
 normal file system.
 
 You'll need to enable VFS caching if you want, for example, to read
@@ -51,7 +51,7 @@ closed so if rclone is quit or dies with open files then these won't
 get written back to the remote.  However they will still be in the on
 disk cache.
 
-#### --vfs-cache-mode off ####
+#### --vfs-cache-mode off
 
 In this mode the cache will read directly from the remote and write
 directly to the remote without caching anything on disk.
@@ -66,7 +66,7 @@ This will mean some operations are not possible
   * Open modes O_APPEND, O_TRUNC are ignored
   * If an upload fails it can't be retried
 
-#### --vfs-cache-mode minimal ####
+#### --vfs-cache-mode minimal
 
 This is very similar to "off" except that files opened for read AND
 write will be buffered to disks.  This means that files opened for
@@ -79,7 +79,7 @@ These operations are not possible
   * Files opened for write only will ignore O_APPEND, O_TRUNC
   * If an upload fails it can't be retried
 
-#### --vfs-cache-mode writes ####
+#### --vfs-cache-mode writes
 
 In this mode files opened for read only are still read directly from
 the remote, write only and read/write files are buffered to disk
@@ -89,14 +89,14 @@ This mode should support all normal file system operations.
 
 If an upload fails it will be retried up to --low-level-retries times.
 
-#### --vfs-cache-mode full ####
+#### --vfs-cache-mode full
 
 In this mode all reads and writes are buffered to and from disk.  When
 a file is opened for read it will be downloaded in its entirety first.
 
 This may be appropriate for your needs, or you may prefer to look at
 the cache backend which does a much more sophisticated job of caching,
-including caching directory heirachies and chunks of files.q
+including caching directory hierarchies and chunks of files.
 
 In this mode, unlike the others, when a file is written to the disk,
 it will be kept on the disk after it is written to the remote.  It