Adding optional trailing .8 for has_lib searches to prevent false negatives for JPEG lib

[twolfson]

This patch adds the conditional for a .8 ending to the libjpeg.so file.

Debug notes

I recently moved to a new laptop on Linux Mint 14 Cinnamon and was running into the same issues as #254.

I tried moving back to the old version of Cairo, 1.10.2, which had worked on my older machine but no luck. I verified multiple times that I had the proper apt-get dependencies met as listed in the wiki.

After some more debugging, I found that ./util/has_lib.sh jpeg was returning false when it should be true. Upon grepping my ldconfig, I found the following:

$ ldconfig -p | grep jpeg
    libopenjpeg.so.2 (libc6,x86-64) => /usr/lib/x86_64-linux-gnu/libopenjpeg.so.2
    libmjpegutils-1.9.so.0 (libc6,x86-64) => /usr/lib/libmjpegutils-1.9.so.0
    liblavjpeg-1.9.so.0 (libc6,x86-64) => /usr/lib/liblavjpeg-1.9.so.0
    libjpeg.so.8 (libc6,x86-64) => /usr/lib/x86_64-linux-gnu/libjpeg.so.8
    libjpeg.so.8 (libc6) => /usr/lib/i386-linux-gnu/libjpeg.so.8

As a result, I added in my conditional, re-built, and everything magically went back to working.

[gauze]

I had to add .62 to mine to get it to link against that version

[kangax]

This should be now fixed with #327

[twolfson]

Awesome =)