message: Add --libs-only convenience option
diff: @@ -65,8 +65,10 @@ Usage: $0 [OPTION]... [VAR=VALUE]...
  --no-io build without I/O module
  --no-python build without python binding
  --no-summary do not print configuration before building
  - --core-only sets no-examples, no-opencl, no-openssl,
  - no-tools, no-python, and no-io
  + --libs-only sets no-examples, no-tools, no-python,
  + and no-unit-tests
  + --core-only same as libs-only but also adds sets no-opencl,
  + no-openssl, and no-io
  Debugging:
  --with-runtime-checks build with requirement checks at runtime
  @@ -386,13 +388,15 @@ while [ $# -ne 0 ]; do
  --no-summary)
  append_cache_entry CAF_NO_SUMMARY BOOL yes
  ;;
  + --libs-only)
  + for var in CAF_NO_TOOLS CAF_NO_PYTHON CAF_NO_EXAMPLES CAF_NO_UNIT_TESTS; do
  + append_cache_entry $var BOOL yes
  + done
  + ;;
  --core-only)
  - append_cache_entry CAF_NO_TOOLS BOOL yes
  - append_cache_entry CAF_NO_IO BOOL yes
  - append_cache_entry CAF_NO_PYTHON BOOL yes
  - append_cache_entry CAF_NO_EXAMPLES BOOL yes
  - append_cache_entry CAF_NO_OPENCL BOOL yes
  - append_cache_entry CAF_NO_OPENSSL BOOL yes
  + for var in CAF_NO_TOOLS CAF_NO_PYTHON CAF_NO_EXAMPLES CAF_NO_UNIT_TESTS CAF_NO_IO CAF_NO_OPENCL CAF_NO_OPENSSL ; do
  + append_cache_entry $var BOOL yes
  + done
  ;;
  --dev-mode)
  append_cache_entry CMAKE_BUILD_TYPE STRING Debug
  