Log - Message logging API
-------------------------

This interface is designed in such way that code that wants to logg a massage can do so with one call and don't worry
about where it may turn up and what format it should use etc. +
All this is setup trough one function call idealy in the beginning of a process.

Macros
~~~~~~

`LOG_INFO`::
    Information, Someone thinks you may find this important.
    
`LOG_WARN`::
    Warning, just a warning. can be ignored if you simply just don't care about it.
    
`LOG_CRIT`::
    Critical condition, some things may not work as supposed to.
    
`LOG_DEBUG`::
    Debug level, messages that is usefull when debugging.
    
`LOG_ALL`::
    All of the above.

Functions
~~~~~~~~~

`init_log()`::
Initialize the logging functionality, 'level' is a bitmask of the LOG_* contansts defining what types of messages should be logged. +
if 'path' is a writeable directory, output will be written to files in that directory otherwise `stderr` is used.
+
----
init_log(LOG_INFO | LOG_WARN, NULL);
----
+
Will log info and warning messages to `stderr`.

`logstrtolvl()`::
    returns the LOG_* equivalent of a string representation.

`loglvltostr()`::
    returns the string representation of a LOG_* constant.

`logmsg()`::
logs a message, 'level' should be a LOG_* constant for what level the message is for. +
the rest of the arguments is a variable argument list and behaves like `printf()`
+
----
logmsg(LOG_INFO, "this is an integer: %i", 12);
logmsg(LOG_INFO, "this is just a message");
----
+

NOTE: No newline at the end of the message is needed.

`logerrno`::
like `perror()`, logs an message by the 'errno' number. +
if 'prefix' is not `NULL` and points to a string that is not zero length, the message will be prepended whit 'prefix' followed by a colon and a space.