[icu] Add tools

[NancyLi1013]

Currently, the executables generated in _vcpkg\buildtrees\icu\x64-windows-rel\bin are not provided in vcpkg.
Some ports require some of these executables to build with ICU support enabled.

So I add these to tools/icu directory.

Fix #11782

Note: No feature needs to test.

[rleigh-codelibre]

Tested this branch with VS2019 Community and Xerces-C++ master with -Dtranscoder=icu -Dmsgloader=icu and it successfully detected all the needed libraries and executables:

//ICU data library (debug)
ICU_DATA_LIBRARY_DEBUG:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/debug/lib/icudtd.lib

//ICU data library (release)
ICU_DATA_LIBRARY_RELEASE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/lib/icudt.lib

//ICU derb executable
ICU_DERB_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/derb.exe

//ICU genbrk executable
ICU_GENBRK_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/genbrk.exe

//ICU genccode executable
ICU_GENCCODE_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/genccode.exe

//ICU gencfu executable
ICU_GENCFU_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/gencfu.exe

//ICU gencmn executable
ICU_GENCMN_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/gencmn.exe

//ICU gencnval executable
ICU_GENCNVAL_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/gencnval.exe

//ICU gendict executable
ICU_GENDICT_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/gendict.exe

//ICU gennorm2 executable
ICU_GENNORM2_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/gennorm2.exe

//ICU genrb executable
ICU_GENRB_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/genrb.exe

//ICU gensprep executable
ICU_GENSPREP_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/gensprep.exe

//ICU icu-config executable
ICU_ICU-CONFIG_EXECUTABLE:FILEPATH=ICU_ICU-CONFIG_EXECUTABLE-NOTFOUND

//ICU icuinfo executable
ICU_ICUINFO_EXECUTABLE:FILEPATH=ICU_ICUINFO_EXECUTABLE-NOTFOUND

//ICU icupkg executable
ICU_ICUPKG_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/icupkg.exe

//ICU include directory
ICU_INCLUDE_DIR:PATH=/Users/rleigh/code/vcpkg/installed/x64-windows/include

//ICU makeconv executable
ICU_MAKECONV_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/makeconv.exe

//ICU pkgdata executable
ICU_PKGDATA_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/pkgdata.exe

//ICU uconv executable
ICU_UCONV_EXECUTABLE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/tools/icu/uconv.exe

//ICU uc library (debug)
ICU_UC_LIBRARY_DEBUG:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/debug/lib/icuucd.lib

//ICU uc library (release)
ICU_UC_LIBRARY_RELEASE:FILEPATH=/Users/rleigh/code/vcpkg/installed/x64-windows/lib/icuuc.lib

So the change looks fine as is. But if you need to have the tools optional as a [tools] component that would also work fine.

[NancyLi1013]

@rleigh-codelibre
Thanks for your test and suggestion.
It must be better if we add tools as a feature for icu. But since icu is not built via CMake. So I have no idea about how to implement this. Do you have any suggestions?

[NancyLi1013]

If there are no any suggestions about this, I will add tools as current statues.

[rleigh-codelibre]

I think this PR is fine as it is in terms of adding the tool support.

Making it a separate component would be nice, but I'll have to have a dig into the vcpkg internals to see how to do it. Could that be done as a followup?

[NancyLi1013]

Of course you can do that. In my opinion, we can consider to add it as a separate component in the future. Now what we need to do is to make sure that it can be used.

[rleigh-codelibre]

My testing above with the CMake FindICU module using find_package(ICU) demonstrated that all the executables are correctly found and are properly functional in the context of a Xerces-C++ package build.