various small problems with documentation

[boucman]

while going through the tutorials I found a couple of problems

in the "how to install" tutorial

• there is a R2 release for juno, which works fine. You still point to R1
• the screenshot has 3 features, but when I actually did it there was only one. this is slightly confusing

in the "how to run" tutorial

• you say that the sftp server will be in the next release, it is now available

in the "remote debug" tutorial

• the option "gdb for the host" needs to be configured in buildroot, since it's the cross-gdb and not the native gdb that is used

overall this thing is awesome, thx a lot for the contribution

[tpetazzoni]

Thanks a lot for your feedback. We've fixed all those issues in the tutorials.