HPCC-27104 Add vcpkg submodule

Add support for nuget caching of third-party packages

Signed-off-by: Gordon Smith <GordonJSmith@gmail.com>

.gitmodules

@@ -70,3 +70,6 @@
 [submodule "common/remote/hooks/git/libgit2"]
 	path = common/remote/hooks/git/libgit2
 	url = https://github.com/hpcc-systems/libgit2.git
+[submodule "vcpkg"]
+	path = vcpkg
+	url = https://github.com/hpcc-systems/vcpkg.git

cmake_modules/commonSetup.cmake

@@ -676,26 +676,40 @@ IF ("${COMMONSETUP_DONE}" STREQUAL "")
         message(STATUS "Using externals directory at ${EXTERNALS_DIRECTORY}")
     endif()
 
-  IF ( NOT MAKE_DOCS_ONLY )
-      IF ("${EXTERNALS_DIRECTORY}" STREQUAL "")
+    IF ( NOT MAKE_DOCS_ONLY )
+      FIND_PACKAGE(BISON)
+      FIND_PACKAGE(FLEX)
+      IF ( BISON_FOUND AND FLEX_FOUND )
+        SET(BISON_exename ${BISON_EXECUTABLE})
+        SET(FLEX_exename ${FLEX_EXECUTABLE})
         IF (WIN32)
-          SET(bisoncmd "win_bison")
-          SET(flexcmd "win_flex")
+          SET(bisoncmd ${BISON_exename})
+          SET(flexcmd ${FLEX_exename})
         ELSE()
           SET(bisoncmd "bison")
           SET(flexcmd "flex")
         ENDIF()
-      ELSE()
-        IF (WIN32)
-          SET(bisoncmdprefix "call")
-          SET(flexcmdprefix "call")
-          SET(bisoncmd "${EXTERNALS_DIRECTORY}\\bison\\bison.bat")
-          SET(flexcmd "${EXTERNALS_DIRECTORY}\\bison\\flex.bat")
-        ELSE ()
-          SET(bisoncmd "${EXTERNALS_DIRECTORY}/bison/bison")
-          SET(flexcmd "${EXTERNALS_DIRECTORY}/bison/flex")
+      ELSE ()
+        IF ("${EXTERNALS_DIRECTORY}" STREQUAL "")
+          IF (WIN32)
+            SET(bisoncmd "win_bison")
+            SET(flexcmd "win_flex")
+          ELSE()
+            SET(bisoncmd "bison")
+            SET(flexcmd "flex")
+          ENDIF()
+        ELSE()
+          IF (WIN32)
+            SET(bisoncmdprefix "call")
+            SET(flexcmdprefix "call")
+            SET(bisoncmd "${EXTERNALS_DIRECTORY}\\bison\\bison.bat")
+            SET(flexcmd "${EXTERNALS_DIRECTORY}\\bison\\flex.bat")
+          ELSE ()
+            SET(bisoncmd "${EXTERNALS_DIRECTORY}/bison/bison")
+            SET(flexcmd "${EXTERNALS_DIRECTORY}/bison/flex")
+          ENDIF()
         ENDIF()
-      ENDIF()
+      ENDIF ()
 
       IF ("${BISON_VERSION}" STREQUAL "")
         IF (WIN32)

vcpkg

@@ -0,0 +1 @@
+Subproject commit 6114d10957ab676b795a595468fc779f50aba573