Add command module in server

Adding a command module we can accept commands from any API
client application to interact with the server features.
Funcional command aggregation

Install a connect command to the current server
and makes the command available in this client API.
Add sqlite database authentication

In this version a database can be reached by the client API
this database has some authorized users with respective passwords.

obs: this commit assumes that server already
have a correct format database in /var/opt/banco.db
fix: parameters size

user, pass and room parameters need more size.
kind of gross think to do :P
fixes: Removes anti patterns and adds a permissive license

Various miscellaneous and esthetics changes to remove anti patterns from the
code. At this point either a permissive license was added.
remove: delete cmd.h

the source was moved to server.h
Databese global descriptor

Changes the database to a global descriptor allowing the database to be opened
only once and is kept open all the way down.
Add SQLITE macro

define a macro to sqlite3 functions, and change the
defines to server.h
Add command to send private messages to users

adds capability of send direct messages to one specific user.
This message is treated as a /secret and will not be shown to others users in
the same room.
Changes were made in the client and server. The protocol must be respect.
Another architectures changes must be made probably soon.
Minors: add fixes to antipaterns

I am still making some antipatern mistakes, actualy the client has lots of this
a will continue to remove some of them frequently.