Adds a new compiler family MSVC_INTEL.

This enables using the Intel compiler toolchain within Visual Studio.

Also updates the blt_append_compiler_flag() macro to accept the MSVC_INTEL
keyword.  When provided, it will override the MSVC keyword within Visual
Studio configurations of blt.

cmake/BLTMacros.cmake

@@ -617,24 +617,27 @@ endmacro(blt_add_benchmark)
 
 ##------------------------------------------------------------------------------
 ## blt_append_custom_compiler_flag( 
-##                    FLAGS_VAR flagsVar     (required)
-##                    DEFAULT   defaultFlag  (optional)
-##                    GNU       gnuFlag      (optional)
-##                    CLANG     clangFlag    (optional)
-##                    INTEL     intelFlag    (optional)
-##                    XL        xlFlag       (optional)
-##                    MSVC      msvcFlag     (optional)
+##                    FLAGS_VAR  flagsVar       (required)
+##                    DEFAULT    defaultFlag    (optional)
+##                    GNU        gnuFlag        (optional)
+##                    CLANG      clangFlag      (optional)
+##                    INTEL      intelFlag      (optional)
+##                    XL         xlFlag         (optional)
+##                    MSVC       msvcFlag       (optional)
+##                    MSVC_INTEL msvcIntelFlag  (optional)
 ## )
 ##
 ## Appends compiler-specific flags to a given variable of flags
 ##
-## If a custom flag is given for the current compiler, we use that,
+## If a custom flag is given for the current compiler, we use that.
 ## Otherwise, we will use the DEFAULT flag (if present)
+## When using the Intel toolchain within visual studio, we use the 
+## MSVC_INTEL flag, when provided, with a fallback to the MSVC flag.
 ##------------------------------------------------------------------------------
 macro(blt_append_custom_compiler_flag)
 
    set(options)
-   set(singleValueArgs FLAGS_VAR DEFAULT GNU CLANG INTEL XL MSVC)
+   set(singleValueArgs FLAGS_VAR DEFAULT GNU CLANG INTEL XL MSVC MSVC_INTEL)
    set(multiValueArgs)
 
    # Parse the arguments
@@ -655,7 +658,9 @@ macro(blt_append_custom_compiler_flag)
       set (${arg_FLAGS_VAR} "${${arg_FLAGS_VAR}} ${arg_INTEL} " )
    elseif( DEFINED arg_GNU AND COMPILER_FAMILY_IS_GNU )
       set (${arg_FLAGS_VAR} "${${arg_FLAGS_VAR}} ${arg_GNU} " )
-   elseif( DEFINED arg_MSVC AND COMPILER_FAMILY_IS_MSVC )
+   elseif( DEFINED arg_MSVC_INTEL AND COMPILER_FAMILY_IS_MSVC_INTEL )
+      set (${arg_FLAGS_VAR} "${${arg_FLAGS_VAR}} ${arg_MSVC_INTEL} " )
+   elseif( DEFINED arg_MSVC AND (COMPILER_FAMILY_IS_MSVC OR COMPILER_FAMILY_IS_MSVC_INTEL) )
       set (${arg_FLAGS_VAR} "${${arg_FLAGS_VAR}} ${arg_MSVC} " )
    elseif( DEFINED arg_DEFAULT )
       set (${arg_FLAGS_VAR} "${${arg_FLAGS_VAR}} ${arg_DEFAULT} ")

cmake/SetupCompilerOptions.cmake

@@ -72,7 +72,12 @@ endif()
 if("${CMAKE_BUILD_TOOL}" MATCHES "(msdev|devenv|nmake|MSBuild)")
     set(COMPILER_FAMILY_IS_MSVC 1)
     message(STATUS "Compiler family is MSVC")
-
+
+    if(CMAKE_GENERATOR_TOOLSET AND "${CMAKE_GENERATOR_TOOLSET}" MATCHES "Intel")
+        set(COMPILER_FAMILY_IS_MSVC_INTEL 1) 
+        message(STATUS "Toolset is ${CMAKE_GENERATOR_TOOLSET}")
+    endif()
+
 elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
     set(COMPILER_FAMILY_IS_GNU 1)
     message(STATUS "Compiler family is GNU")
@@ -92,6 +97,8 @@ elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Intel")
 endif()
 
 
+
+
 ################################################
 # Support for extra compiler flags and defines
 ################################################
@@ -263,17 +270,17 @@ message(STATUS "Standard C++${CMAKE_CXX_STANDARD} selected")
 
 blt_append_custom_compiler_flag(
     FLAGS_VAR BLT_ENABLE_ALL_WARNINGS_FLAG
-     DEFAULT "-Wall -Wextra"
-     CLANG   "-Wall -Wextra" 
-                    # Additional  possibilities for clang include: 
-                    #       "-Wdocumentation -Wdeprecated -Weverything"
-     MSVC    "/W4"
-                    # Additional  possibilities for visual studio include:
-                    # "/Wall /wd4619 /wd4668 /wd4820 /wd4571 /wd4710"
-     XL      ""     # qinfo=<grp> produces additional messages on XL
-                    # qflag=<x>:<x> defines min severity level to produce messages on XL
-                    #     where x is i info, w warning, e error, s severe; default is: 
-                    # (default is  qflag=i:i)
+     DEFAULT    "-Wall -Wextra"
+     CLANG      "-Wall -Wextra" 
+                       # Additional  possibilities for clang include: 
+                       #       "-Wdocumentation -Wdeprecated -Weverything"
+     MSVC       "/W4"
+                       # Additional  possibilities for visual studio include:
+                       # "/Wall /wd4619 /wd4668 /wd4820 /wd4571 /wd4710"
+     XL         ""     # qinfo=<grp> produces additional messages on XL
+                       # qflag=<x>:<x> defines min severity level to produce messages on XL
+                       #     where x is i info, w warning, e error, s severe; default is: 
+                       # (default is  qflag=i:i)
      )
 
 blt_append_custom_compiler_flag(