Add googletest wrap
Add the wrap so tests can be done standalone.
The "'BUILD_SHARED_LIBS': 'ON'" option is needed or else stdplus, which
is indirectly pulled in as a subproject, fails with:
```
subprojects/stdplus/src/meson.build:207:22: ERROR: Can't link non-PIC static library 'gtest' into shared library 'stdplus-gtest'.
Use the 'pic' option to static_library to build with PIC.
```
Change-Id: Ia1847cab885e2b6adb72bec08621f5d154990e79
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/subprojects/googletest.wrap b/subprojects/googletest.wrap
new file mode 100644
index 0000000..56da9ef
--- /dev/null
+++ b/subprojects/googletest.wrap
@@ -0,0 +1,3 @@
+[wrap-git]
+url = https://github.com/google/googletest
+revision = HEAD