Various MATLABWindow commands silently fail (addons, login, etc.)

[Luke Renaud]

In the current MATLAB 2018a release on Ubuntu 18.04, multiple UI dialog windows are inoperable due to a bundled glib2 incompatibility.

Specific Problems:
calling `appdesigner` at the matlab command window produces errors
the "add-ons" UI button and "log in" UI buttons produce no visible action
any calls involving `bin/glxa64/MATLABWindow` produce errors

Proposed Fix:
The solution is to simply disable the bundled libglib-2.0.so library so that the default Ubuntu library is used. Adding something in the postinst script to handle this such as the following should fix the issue. It is not clear if this issue will persist in future versions of MATLAB.

```
matlab_path="/usr/local/MATLAB/R2018a"
mathworks_glib_file="$(readlink -f "$matlab_path/cefclient/sys/os/glnxa64/libglib-2.0.so.0")"
mv "$mathworks_glib_file" "${mathworks_glib_file}.bak"

```