Added implementation for issue 447

[maik-s]

This pull request implements a solution for #447

Two new command line options are introduced:

-or, -omit-raw                    omit raw requests/responses from output
-ob, -omit-body                   omit response body from output

The following data illustrates how much space these options save:

4,6M Mai 30 13:34 /tmp/projectdiscovery.io.json
2,3M Mai 30 13:36 /tmp/projectdiscovery.io-omit-body.json
2,3M Mai 30 13:36 /tmp/projectdiscovery.io-omit-raw.json
4,2K Mai 30 13:36 /tmp/projectdiscovery.io-omit-raw-omit-body.json

Using either one of the options roughly reduces the output size to half of the complete output file.
When using both command line options, only the meta data are left, which are useful for further processing.

[ehsandeep]

thank you @maik-s for adding these options.