Added simple pear language plugin.

Uses `pear info PEAR` to get info on PEAR itself.

```json
  "languages": {
    "php": {
      "version": "5.2.10-2ubuntu6.5",
      "builddate": "May 21 2010 06:28:46"
    },
    "perl": {
      "version": "5.10.1",
      "archname": "x86_64-linux-gnu-thread-multi"
    },
    "python": {
      "version": "2.6.5",
      "builddate": "Apr 16 2010, 13:57:41"
    },
    "pear": {
      "version": "1.6.1",
      "builddate": "2007-06-23 18:11:06"
    },
    "ruby": {
      // blah
  },
```