Match darwin13 in configure.ac

Mike and Seven said this is desirable.
Cleanup whitespace
Revert "Cleanup whitespace"

Too much was staged accidentally on that last commit.

This reverts commit f1126272424483efd6d8db7741dfc9949492e026.
Cleanup whitespace
Update some modules to use CPPFLAGS

These modules use curl and we'll be adding in some bits to the
CPPFLAGS.
Require libcurl as a system dependency

This purges libcurl from our tree and requires it to be present on the
system for building and running FreeSWITCH.

FS-353
Add curl auto PKG_CONFIG_PATH handling for OS X

FS-353
Export paths touched by path_push_unique()

FS-353
FS-353: add PKG_CONFIG_PATH for keg only curl from homebrew on mac
Allow older versions of curl to be used

...at your own risk.  cURL has had some serious security issues over
the years, so if you're using an ancient version, I hope that you're
receiving security patches from your vendor.

The version set here is to accommodate CentOS 6.
FS-6346
Clean up bash rc
FS-6294 DragonFly requires this also.
clean up esl module makefile by MikeJ
reswig
1/2 of automake for esl perl, at least we have configure detecting things now
fix typo
don't install test programs
add #!
fully automake esl perlmod