Added support for include mechanism in the main.cfg file. An [include] block can be added in main.cfg, like this:

[include]
servicename1 = /my/service/repository/service1.zcfg
servicename2 = /my/service/repository/service2.zcfg
...

The word "include" thus has a special (reserved) meaning, just as "main" does. If necessary, a user may change "include" to something else by redefining the IMPORTSERVICE macro.

The service name (left hand side) should match the [service name] in the config (zcfg) file, but the path/file name (right hand side) may be arbitrary.

When handling requests, Zoo will first check if there is an [include] block, then recursively search the working directory (CWD) and subdirectories as before. If an [include]d service happens to be located in a CWD (sub)directory, it will be published by its [include]d name.

As currently implemented, Zoo will search CWD for the library files of [include]d services if the libPath parameter is not set (note that presently only C and PHP services support the libPath parameter).

Added new function (zoo_path_compare) to check if two path strings refer to the same physical file. It should handle symbolic links (typically, Linux/Unix?) and different path separators (typically, Windows).