Allow PACKAGE_VERSION override

[bneradt]

Allow a user to override PACKAGE_VERSION via -DPACKAGE_VERSION= on the commandline.

[cmcfarlen]

Consider this approach instead:

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b26d0e209..73f66e5a4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,7 +29,10 @@ project(ats VERSION 10.2.0)
 set(TS_VERSION_MAJOR ${PROJECT_VERSION_MAJOR})
 set(TS_VERSION_MINOR ${PROJECT_VERSION_MINOR})
 set(TS_VERSION_MICRO ${PROJECT_VERSION_PATCH})
-set(TS_VERSION_STRING ${TS_VERSION_MAJOR}.${TS_VERSION_MINOR}.${TS_VERSION_MICRO})
+set(TS_VERSION_STRING
+    ${TS_VERSION_MAJOR}.${TS_VERSION_MINOR}.${TS_VERSION_MICRO}
+    CACHE STRING "The version string"
+)
 math(EXPR TS_VERSION_NUMBER "${TS_VERSION_MAJOR} * 1000000 + ${TS_VERSION_MINOR} * 1000 + ${TS_VERSION_MICRO}")

 # We make this a cache entry so that it can be configured to different values

TS_VERSION_STRING is also used in several configure_file calls to expand in header files etc. Overriding this cmake var will cascade through the build.

[cmcfarlen]

consider overriding TS_VERSION_STRING instead.