Fixing debian build files including automated database setup

Tested workflow on wheezy:

```
$ sudo aptitude install -y apache2 mysql-server php5 php5-mysql build-essential libmysqlclient-dev libssl-dev libbz2-dev libpcre3-dev libdbi-perl libarchive-zip-perl libdate-manip-perl libdevice-serialport-perl libmime-perl libpcre3 libwww-perl libdbd-mysql-perl libsys-mmap-perl yasm subversion automake autoconf libjpeg8-dev libjpeg8 apache2-mpm-prefork libapache2-mod-php5 php5-cli libphp-serialization-perl libgnutls-dev libjpeg8-dev libavcodec-dev libavformat-dev libswscale-dev libavutil-dev libv4l-dev libtool ffmpeg libnetpbm10-dev libavdevice-dev libmime-lite-perl dh-autoreconf dpatch;
$ ./bootstrap.sh;
$ ln -s distros/debian;
$ dpkg-checkbuilddeps; 
$ dpkg-buildpackage;
```

I've integrated the postinst script shipped with v 1.25.0 under debian which includes automated provisioning for the zm database.

HTH