Address CRAN feedback

• Avoid starting the description with the package name.
• Remove if(FALSE) blocks from help files to fix "unexecutable code" warnings (tar_glimpse(), tar_visnetwork(), and tar_watch()).
• Remove commented code in the examples (tar_edit(), tar_watch_ui(), and tar_watch_server()).
• Ensure that all examples, tests, and vignettes do not write to the user's home file space. (Fixed an example of tar_workspace().)