Generated tree too wide with more complicated RA expressions

[MariusAlbrecht]

e.g. the expression
rho eins<-Name(pi Name (Studenten join (pi MatrNr (hoeren join (sigma Titel='Grundzuege'(Vorlesungen join hoeren)))))) join eins!=zwei rho zwei<-Name(pi Name (Studenten join (pi MatrNr (hoeren join (sigma Titel='Grundzuege'(Vorlesungen join hoeren)))))) on the dataset "Kemper Datenbanksysteme" returns the following tree:

when it should return something like this:

this is (as far as i can see) because of the width restriction on the .col-xl-6r class (the second image was obtained by taking a screenshot after setting the 50% to 70%)

at the very least the page should

1. detect the issue and display a warning
2. download/export correctly because that doesnt affect the site ui

[Vedant-Sharma-39]

I think a horizontal scrolling bar or a zoom feature would help.

[rlaiola]

PR #216 should fix these problems.

You can try it out at https://rlaiola.github.io/relax/calc/local/uibk/local/1