[Enhancement] tuner.search_space_summary() should return string object instead implicitly of printing to stdout.

[GhostDog98]

Is your feature request related to a problem? Please describe.
Currently, if i would like to get search_space_summary into a variable, instead of printing to stdout, i need to do the following hack:

old_stdout = sys.stdout # for later
sys.stdout = io.StringIO() # capture stdout
tuner.search_space_summary()  # Print summary of search space to stdout
captured_output = sys.stdout.getvalue() # get the saved value...
sys.stdout = old_stdout # restore old stdout

This seems overly complex, and it is unintuitive behaviour that calling search_space_summary implicitly prints.
Additionally, in my opinion, it breaks PEP20 rule 2; that Explicit is better than implicit.
Describe the solution you'd like
I propose that instead of:

We essentially have:

Describe alternatives you've considered
Rename the function to print_seach_space_summary() to make it explicit to the programmer that this prints directly to STDOUT.
This, however, would still leave no "clean" way to get the search space summary programatically.