Replace hardcoded context roots from app-cfg.js

When deploying the Flowable UI Apps under a different context root from the default /flowable-*, it is possible to make everything work using changes in property files (e.g. flowable.common.app.idm-url is configurable), except for one party pooper: the file ./src/main/resources/static/scripts/app-cfg.js has hardcoded context root strings:

FLOWABLE.CONFIG = {
        'onPremise' : true,
        'contextRoot' : '/flowable-idm',
        'webContextRoot' : '/flowable-idm',
    'datesLocalization' : false
};

If these static strings weren’t there, then the app wars could be transparently deployed under a different context root. Currently, putting an app on a different context root requires modifying the war file.

[tijsrademakers]

Thanks for the ping, this is implemented with the PR indeed.

[n0mer]

@jbarrez @tijsrademakers what do you think, #1100 solved this?