Add log timeout

The default (5000) timeout of gen_server was not enough
Maybe due to network or port driver issues
I'd like to specify higher timeout value
Fix double-free on bad 'open', fixes issue #3
Merge pull request #4 from tcseke/log-timeout

Add log timeout
indentation overhaul
revise driver to use port_control, and add close/1

Use port_control and port_call instead of just port_command to communicate
with the port driver. The port_control and port_call functions include a
command integer argument that makes it easy to send specific commands to
the driver, rather than encoding the commands as atoms in external
format. They also allow for the easy return of simple terms in their
preallocated return buffers. They also allow simple constants to be
returned from the driver for badarg and other general errors. The log
function still uses port_command, but sends an iolist for priority and
message data rather than encoding to external format.

Change open to return a new port, and change the log functions to take the
log port returned from open as its first argument.

Add a new variant of the log function that takes a format string and a list
of format arguments. Drop the timeout argument to log, since it no longer
is meaningful.

Add a close/1 function to close the log.

Modify the determination of the path to the driver shared library, making
it match idiomatic code used for NIFs and drivers in other components.

Add checking of the return values from the ei encoding and decoding
functions in the driver code.

Use driver_alloc and driver_free in the driver code rather than malloc and
free. Also add checks for memory allocation failures.

Use static initialization for the ErlDrvEntry struct. Remove the creation
of driver atom constants that were no longer used.

Add a test to verify that logging on a log that's already been closed
returns an error.
Update docs, bump version to 1.0.0
Merge branch 'vinoski-sv-driver-tweaks'
Fix compile error on GCC

Error was: 

c_src/syslog_drv.c:92: error: 'int32_t' undeclared (first use in this function)

on

cc (GCC) 4.2.1 20070831 patched [FreeBSD]
Use uint32_t instead of int32_t
Merge pull request #6 from hukl/master

Fixed a compiler error on FreeBSD and corrected wrong integer type
Roll version 1.0.1