Support for IGN RAF09 geoid

This is a copy of pull request #38 due to an error in my fork 
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Dear Tomoji,
As you proposed I've made the code compatible with c89 (with gcc-4.9 -std=c89 -pedantic -g -c -Wall there is no warning)
Also marc60dev told me that he could not compile under Embarcadero C++ Builder XE2, it was due to the lack of fgetln . So I rewrote raf09_getline for using only ANSI C function. Android and MacOS have very fast fgetln implementation (with low level stream manipulation) so I let my old code in a #define block. 
Also I add some checks in the parsing process for being more robust to bad geoid models.

As requested by marc60dev I modified the C++ builer combo box in RTKNAVI and RTKPOST for using under Windows, this is coming from pull request #41 .

Finally I modified the test/Makefile for downloading automatically the two geoid models, the Makefile is for Linux but may be easily adapted.