Actually fix the localedef command

[Lnaden]

This is quite the fix to get modern TexLive working in CentOS 6...

This is step 1 to getting our new images based on conda-forge working again (to then ultimatley get our builds working with conda-build >= 3.0)

The localedata and localedef lines are there for the following conditions:

• 1. Conda Forge sets en_US.UTF-8 as LANG in its env
• 2. Adding the new GLIBC to LD_LIBRARY_PATH causes Perl to try and use it
• 3. The Locales are not built by default with a GLIBC
• 4. Perl then complains because the UTF-8 Locale is not compiled
• 5. Running localedef uses the system one, and there does not appear to be a way to change the new one's pointer
• 6. Finding the exact combination of commands to get the new localedef to work required digging through the Makefile
• 7. These 2 commands create the pre-requisite folder to drop the locale file, and then compile ONLY en_US.UTF-8
• 8. Using the built in Makefile commands installs all of the locales, which is >100MB
• locale-gen does not exist on CentOS 6
• Debugging this was a pain, especially since if you unset LANG, the errors go away (but may cause texlive to segfault later)

[Lnaden]

I just finished some local tests, I'm just going to merge this so I can keep the builds going