update readme

README.md

 # DoubleTankLab
 
-This module is used for the doubletank lab.
-It currently works for julia v0.6 only.
+This module contains the simulation only version of the doubletank lab.
+It currently works for julia v1.3 (at least).
 
 ## Installation
 In Julia, install with
 ```julia
-Pkg.clone("https://gitlab.control.lth.se/processes/LabProcesses.jl.git")
-Pkg.clone("https://gitlab.control.lth.se/labdev/LabConnections.jl.git")
-Pkg.clone("https://gitlab.control.lth.se/processes/LabGUI.jl.git")
-Pkg.clone("https://gitlab.control.lth.se/processes/DoubleTankLab.jl.git")
+] add https://gitlab.control.lth.se/processes/DoubleTankLab.jl#simonlyfix
 ```
-
-## Usage
-After running 
-```julia
-using DoubleTankLab
-```
-the method `runprocess()` runs the tank lab GUI with a physical process. Running `runsimulation()` runs it as a simulation.
-The GUI is then accessible via browser, by default at <http://0.0.0.0:8000>.