Fix IGNITION_MATH_XXX_VERSION

[caguero]

This was the generated content before this patch:

/* Config.hh. Generated by CMake for ignition-math. */

/* Version number */
#define IGNITION_MATH_MAJOR_VERSION 
#define IGNITION_MATH_MINOR_VERSION 
#define IGNITION_MATH_PATCH_VERSION 

#define IGNITION_MATH_VERSION "6.4"
#define IGNITION_MATH_VERSION_FULL "6.4.0"

#define IGNITION_MATH_VERSION_NAMESPACE v6

#define IGNITION_MATH_VERSION_HEADER "Ignition math, version 6.4.0\nCopyright (C) 2014 Open Source Robotics Foundation.\nReleased under the Apache 2.0 License.\n\n"

/* #undef IGNITION_MATH_BUILD_TYPE_PROFILE */
/* #undef IGNITION_MATH_BUILD_TYPE_DEBUG */
/* #undef IGNITION_MATH_BUILD_TYPE_RELEASE */

And now with the fix:

/* Config.hh. Generated by CMake for ignition-math. */

/* Version number */
#define IGNITION_MATH_MAJOR_VERSION 6
#define IGNITION_MATH_MINOR_VERSION 4
#define IGNITION_MATH_PATCH_VERSION 0

#define IGNITION_MATH_VERSION "6.4"
#define IGNITION_MATH_VERSION_FULL "6.4.0"

#define IGNITION_MATH_VERSION_NAMESPACE v6

#define IGNITION_MATH_VERSION_HEADER "Ignition math, version 6.4.0\nCopyright (C) 2014 Open Source Robotics Foundation.\nReleased under the Apache 2.0 License.\n\n"

/* #undef IGNITION_MATH_BUILD_TYPE_PROFILE */
/* #undef IGNITION_MATH_BUILD_TYPE_DEBUG */
/* #undef IGNITION_MATH_BUILD_TYPE_RELEASE */

[codecov]

Codecov Report

Merging #151 into ign-math6 will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           ign-math6     #151   +/-   ##
==========================================
  Coverage      99.25%   99.25%           
==========================================
  Files             59       59           
  Lines           5788     5788           
==========================================
  Hits            5745     5745           
  Misses            43       43           

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[scpeters]

@osrf-jenkins run tests please