Pass --batch to gdb
Pass --batch to gdb

In one of my travis builds, I was surprised to find that the gdb
pager was in use and caused travis to time out.  Adding `--batch`
to the gdb invocation will disable the pager.  Note that the
`-ex q` is retained, to make sure gdb exits with status 0, just in
case `set -e` is in effect somehow.

aidancully/rust,GBGamer/rust,aidancully/rust,GBGamer/rust,graydon/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,GBGamer/rust,aidancully/rust,graydon/rust,graydon/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,aidancully/rust