Adding lspci vtable for linux

This pull request attempts to partially resolve #221 . Also added libudev-dev & libudev-devel dependency for ubuntu and centos correspondingly in provisions.sh for it to work on a fresh installation attempt. A sample out is below:

```
osquery> select * from lspci;

+--------------+--------------------------+---------------------------------+-------------------------------------------------+
| slot         | device_class             | vendor                          | model                                           |
+--------------+--------------------------+---------------------------------+-------------------------------------------------+
| 0000:00:00.0 | Bridge                   | Intel Corporation               | Haswell DRAM Controller                         |
| 0000:00:01.0 | Bridge                   | Intel Corporation               | Haswell PCI Express x16 Controller              |
| 0000:01:00.0 | Display controller       | NVIDIA Corporation              | GK106M [GeForce GTX 770M]                       |
| 0000:00:02.0 | Display controller       | Intel Corporation               | Haswell Integrated Graphics Controller          |
| 0000:00:03.0 | Multimedia controller    | Intel Corporation               | Haswell HD Audio Controller                     |
| 0000:00:14.0 | Serial bus controller    | Intel Corporation               | Lynx Point USB xHCI Host Controller             |
| 0000:00:16.0 | Communication controller | Intel Corporation               | Lynx Point MEI Controller                       |
| 0000:00:1a.0 | Serial bus controller    | Intel Corporation               | Lynx Point USB Enhanced Host Controller         |
| 0000:00:1b.0 | Multimedia controller    | Intel Corporation               | Lynx Point High Definition Audio Controller     |
| 0000:00:1c.0 | Bridge                   | Intel Corporation               | Lynx Point PCI Express Root Port                |
| 0000:07:00.0 | Network controller       | Intel Corporation               | Dual Band Wireless-AC 7260                      |
| 0000:00:1c.3 | Bridge                   | Intel Corporation               | Lynx Point PCI Express Root Port                |
| 0000:0d:00.0 | Network controller       | Qualcomm Atheros                | AR8161 Gigabit Ethernet                         |
| 0000:00:1c.4 | Bridge                   | Intel Corporation               | Lynx Point PCI Express Root Port                |
| 0000:0e:00.0 | Unassigned class         | Realtek Semiconductor Co., Ltd. | RTS5229 PCI Express Card Reader                 |
| 0000:00:1d.0 | Serial bus controller    | Intel Corporation               | Lynx Point USB Enhanced Host Controller         |
| 0000:00:1f.0 | Bridge                   | Intel Corporation               | Lynx Point LPC Controller                       |
| 0000:00:1f.2 | Mass storage controller  | Intel Corporation               | Lynx Point 6-port SATA Controller 1 [AHCI mode] |
| 0000:00:1f.3 | Serial bus controller    | Intel Corporation               | Lynx Point SMBus Controller                     |
+--------------+--------------------------+---------------------------------+-------------------------------------------------+
osquery> 
```
can you make these `std::string` instead of `char*`?