Improve libcurl configury
Improve libcurl configury

Hardcode use of the curl-config from the 10.4 SDK for MacOSX. Make use
of pkg-config to find libcurl when cross-compiling optional, if no
libcurl package found by pkg-config, use curl-config.

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core