Allow access of guest accounts

[christianlupus]

If the user folder is not writable as typically for a guest account, the cookbook app has hight probability of being non-functional. Yet, there are no useful error messages or ways to tackle the problem. Instead a stacktrace is generated.

This should get this issue covered.

Closes #468

[codecov]

Codecov Report

Merging #506 (f2a8edd) into master (a325d89) will decrease coverage by 0.00%.
The diff coverage is 0.00%.

@@             Coverage Diff             @@
##             master    #506      +/-   ##
===========================================
- Coverage      1.01%   1.01%   -0.01%     
- Complexity      440     444       +4     
===========================================
  Files            13      14       +1     
  Lines          1374    1385      +11     
===========================================
  Hits             14      14              
- Misses         1360    1371      +11     

Flag	Coverage Δ	Complexity Δ
integration	0.00% <0.00%> (ø)	0.00 <1.00> (ø)
unittests	1.01% <0.00%> (-0.01%)	0.00 <1.00> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ	Complexity Δ
lib/Controller/ConfigController.php	0.00% <0.00%> (ø)	7.00 <0.00> (ø)
lib/Controller/MainController.php	0.00% <0.00%> (ø)	40.00 <0.00> (+1.00)
lib/Exception/UserFolderNotWritableException.php	0.00% <0.00%> (ø)	1.00 <1.00> (?)
lib/Service/RecipeService.php	0.00% <0.00%> (ø)	239.00 <0.00> (+2.00)

[christianlupus]

It might be good to wait for #497 to be merged as this will simplify the frontend checks probably.

[seyfeb]

I just checked the functionality (not code) and noticed the following:

• For a narrow window (either in height or width) the border is broken for the folder-selection page

• Selecting a shared folder as a guest doesn’t work for me
  • The selection dialog is opened and it is possible to select the folder
  • After selection nothing happens and a 500 is logged