Merge pull request #1079 from cdituri/cdituri/core/function-nitpick

tag VerifyServices() as static to match prototype
Make special detection macro for root binaries.

The tools that are detected by this macro are meant to be used at
run time, not build time, and therefore do not necessarily have
execute permission for ordinary users. Therefore we cannot use
AC_PATH_PROG.
Merge pull request #1081 from kacfengine/configure-fixes

Make special detection macro for root binaries.
Remove special output for cf-promises in integer conversion
Remove useless banner
Disable users promises if either PAM library or utilities are not found
Merge pull request #1082 from dottedmag/cleanups/allow-no-users-promises

Cleanups/allow no users promises
Add ./testall --gdb option to drop into gdb for acceptance test
extra VERBOSE logging for execresult() and returnszero()
Merge pull request #1084 from dottedmag/feature/testall-gdb-option

Add ./testall --gdb option to drop into gdb for acceptance test
mention --printlog option in testall help
Merge pull request #1085 from tzz/tzz/extra-exec-logging

extra VERBOSE logging for execresult() and returnszero()
Parameterize agent type in parser, remove dependence on THIS_AGENT_TYPE
Remove args.h
Add --eval-functions flag to cf-promises
Do not evaluate functions called from a promise with exlusive ifvarclass

However, do evaluate functions that are rvals of ifvarclass.
Do not evaluate functions called from promises excluded by normal class expressions
per tzz's suggestion in https://github.com/cfengine/core/pull/1028#issuecomment-26712272
maintain backwards compatibility per:
https://github.com/cfengine/core/pull/1028#discussion_r7304957
cleanup per kacfengines' review:
https://github.com/cfengine/core/pull/1028