Disable certificate checking when using wget to fetch solr

Solaris, SmartOS, and FreeBSD are having trouble checking
the certificates of AWS when downloading the solr tgz.  This
commit simply passes `--no-check-certificate` to wget.

Fixes the following error as seen on SmartOS

```
ERROR: cannot verify s3.amazonaws.com's certificate, issued by `/C=US/O=VeriSign, Inc./OU=VeriSign Trust Network/OU=Terms of use at https://www.verisign.com/rpa (c)09/CN=VeriSign Class 3 Secure Server CA - G2':
  Unable to locally verify the issuer's authority.
```