Update the installer script, in time for the Dataverse 4.0.2 (aka 4.1) release

[landreev]

This is the quick-and-dirty installer script I created for TwoRavens for the 4.0 release;
It (potentially) saves the installer some manual copying of files and setting "production" to "true" in 20 places throughout the code, etc.
Things that need to be done:

• a couple of bugs need to be fixed;
• the script that installs R dependencies needs to be updated, so that it can install specified versions of packages - using a list provided by Vito.

(opening this ticket for myself, so that there is a working installer in time for the Dataverse 4.1 release.

[landreev]

OK, fixed the script, committed the changes.
Still need to update the tworavens installation doc in the dataverse guides, to explain/clarify what's going on. This will be handled in #2359.