[LinuxCNC/linuxcnc Issue#566] Tool Table Editor Error

Axis random tool changer simulation edit tool table fails in master.

Here are the steps I follow to reproduce the issue:

1. Run sim.axis radom_tc
2. Click on File > Edit Tool Table

This is what I expected to happen:

Tool Table Editor to appear.

This is what happened instead:

Nothing.

This is the error from the terminal:

Traceback (most recent call last):
File “/usr/lib/python2.7/lib-tk/Tkinter.py”, line 1540, in call
return self.func(*args)
File “/usr/bin/axis”, line 2248, in edit_tooltable
root_window.tk.call(“exec”, *e)
TclError: couldn’t execute “xterm”: no such file or directory

Information about my hardware and software:

* I am using this Linux distribution and version (often, shown by lsb_release -a):
Tested on Linux Mint 18.3 and Debian 9
* I am using this kernel version (shown by uname -a):
* I am running …
* [X] A binary version from linuxcnc.org (including buildbot.linuxcnc.org)
* [ ] A binary I built myself
* [ ] A binary version from some other source besides linuxcnc.org
* I am using this LinuxCNC version (shown in package manager or, for git versions, scripts/get-version-from-git):
* I am using this user interface AXIS:
* I am using this interface hardware vendor and chipset simulator