[ci skip]

Use enum to specify flag value type.

It is possible to create a type-safe version of FlagRegisterer
ctor (as well as some internal gflags classes), that will deduce
type of the new flag automatically.

This results in removing quite a few calls to strcmp() when new
flag is created.

No existing behavior change.

Fix incorrect flag value typename for uint32.

Add missing reference symbol to a function parameter.

fix: Consider Windows-style LRLF in flag parsing

Fix bazel build

complain config.h can't be found.

Add GFLAGS_IS_A_DLL compile option for unit test which includes private config.h.

Support uint32 as flag type

From #99, “Given that there is an unsigned flag type for 64-bit
integers, it is probably reasonable to request/expect the same for
32-bit integers.”

fix #133: Use awk instead of sed which would require different options on OS X

mod: Update doc with new find_package COMPONENTS or subproject use

Fix build of unit test on Ubuntu/Windows by changing include order

These changes improve the CMakeLists.txt of the gflags project to make CMake variables configurable via command-line option -D or super-project settings. Moreover, gflags related variables are only added to the CMake cache when the gflags project is configured as a standalone project. When it is a subproject (cf. #117), the super-project is responsible for setting the configuration variables.

This change set also changes the names of the (exported) target names to gflags[_nothreads]_(static|shared) and the CMake (package) configuration variable names to start with an uppercase prefix "GFLAGS_".

find_package COMPONENTS

This change allows the user to include the gflags project as subtree/
submodule in their own project. In this case, no CMake variables used
to configure the build and installation of the gflags library should be
added to the CMake cache.