Remove getfullyqualifiedname and getusername APIs as they are unused (#25)

Author: adityapatwardhan

src/libpsl-native/src/CMakeLists.txt

@@ -8,10 +8,8 @@ add_library(psl-native SHARED
   getfileowner.cpp
   getcurrentthreadid.cpp
   getcurrentprocessorid.cpp
-  getusername.cpp
   getcomputername.cpp
   getlinkcount.cpp
-  getfullyqualifiedname.cpp
   geterrorcategory.cpp
   getinodedata.cpp
   isfile.cpp

src/libpsl-native/src/getfullyqualifiedname.cpp

@@ -5,10 +5,8 @@ add_executable(psl-native-test
   test-locale.cpp
   test-getuserfrompid.cpp
   test-getcurrentprocessid.cpp
-  test-getusername.cpp
   test-getcomputername.cpp
   test-getlinkcount.cpp
-  test-getfullyqualifiedname.cpp
   test-isdirectory.cpp
   test-isfile.cpp
   test-issymlink.cpp