New docs/openbazaar.1

A new `docs/openbazaar.1`

The content is from [openbazaar.1](https://github.com/OpenBazaar/OpenBazaar/blob/90b8f1748627a11f76f0bd3e57606e71ec0897c6/docs/openbazaar.1) and `openbazaar help`.

NOTES:
- `openbazaar help` content come from [OpenBazaar Beta 3.0](https://github.com/OpenBazaar/OpenBazaar/tree/v0.3.0).
- Please check the content carefully.
- Tested on: Kubuntu 14.04, KDE 4.14.2, Konsole 2.14.2
Merge pull request #1065 from abderraouf-adjal/patch-3

New docs/openbazaar.1
Print path when creating DB.
Create auxiliary setup functions.
Refactor setting up context.

* Factor setting up log file and DB.
* Fix #1011.
* Groom imports.
Group dev mode inititializing code.
Expand tests of argument parser.

* Test for correct parsing of switches, both in long and short form.
* Disable failing test of --log-level for now.
Remove unused uptime timer.

* Remove unused import.
Treat DB and log paths as single entities.

* No reason to store folder and file separately.
* Use os.path.join to be as OS-agnostic as possible.
* --log is no more; use --log-path.
Enforce --log-level to accept an int argument.
Saner Market shutdown.

* Automated mutex acquisition and release.
* Renamed variables to document signal handling API.
Hide arg_to_key inside create_argument_parser.
Move and test ensure_directory.
Stricten tests of DB creation.

* Assert that after executing setup_db, we can connect to DB.
Move launcher tests to proper filename.