Restest

- ADD: comprehensive RESTest documentation
- ENH: path expansion now warns if a value after "=" contains dots, but it is not enclosed in quotes
- FIX: integer checks are now more robust

- ADD: `--log-clean` option to clean the log file before starting the tests
- ADD: request body params now is called `body` by default (you can still use `params` and `data`)
- ADD: returns an error if `body` is not a dictionary
- ENH: now there is a better error explanation when JSON file is not valid
- ENH: now `--version` returns the version number prefixed by `v`

- Now restest can be installed with `pip install restest`

- ADD: every request now returns the response size
- ADD: 'skip' attribute. If set to `true`, the request is skipped
- ADD: new action 'sleep' to wait for a number of milliseconds
- ADD: new 'NOT_EXISTS' / 'NOT_EXIST' condition
- ADD: new special field 'rt:size' to test against the response size
- FIX: fixed a bug that prevented the fields field as a one element list to be expanded correctly

- ADD: --auth-mode option to set the default auth mode (auth or no)
- ENH: better error reporting on corner cases
- ENH: command line options are now sorted in --help

- FIX: merged PR from danielerizzoarchivi for field `data` in postman generator