Explicit hint text will be moved to the instances of the new class
HintTextWidget
HintTextWidget implementation checkpoint
Minor fix on temporary models saving process.
Minor change on relationship editing form, by default random line colors
are enabled.
Changed the hint texts on general config, relationship config and model
restoration form.
Finished the hint text changes on ModelExportForm
Changed the layout of modeldatabasediffform.ui and added hint text
widgets.
Changed the hint texts on relationship editing form
Merge branch 'hint-txts-changes' into model-db-sync