INSTALL.cmake: clarify some flaws/limits in the cmake build

   CMake builds can be configured either from the command line, or from one

   of CMake's GUI's.

Current flaws in the curl CMake build

=====================================

   Missing features in the cmake build:

   - Builds libcurl without large file support

   - It doesn't build src/hugehelp.c which creates the --manual output

   - Can't select which SSL library to build with, only OpenSSL

   - Doesn't build with SCP and SFTP support (libssh2)

   - Doesn't allow different resolver backends (no c-ares build support)

   - No RTMP support built

   - Doesn't allow build curl and libcurl debug enabled

   - Doesn't allow a custom CA bundle path

   - Doesn't allow you to disable specific protocols from the build

   - Doesn't properly enable IPv6 support by default

   - Doesn't find or use krb4 or GSS

   - Rebuilds test files too eagerly, but still can't run the tests

Important notice

==================

   If you got your curl sources from a distribution tarball, make sure to

Command Line CMake

==================

   A command line build of Curl is similar to the autotools build of Curl. It

   A CMake build of curl is similar to the autotools build of curl. It

   consists of the following steps after you have unpacked the source.

       # 1st create an out of source build tree parallel to the curl source

       # tree and change into that directory

       mkdir curl-build

       cd curl-build

       # now run CMake from the build tree, giving it the path to the top of

       # the Curl source tree.  CMake will pick a compiler for you. If you

       # want to specify the compile, you can set the CC environment

       # variable prior to running CMake.

       cmake ../curl

       make

       # currently make test is not implemented

       #make test

       # Install to default location:

       make install

    1. Create an out of source build tree parallel to the curl source

       tree and change into that directory

    $ mkdir curl-build

    $ cd curl-build

    2. Run CMake from the build tree, giving it the path to the top of

       the curl source tree.  CMake will pick a compiler for you. If you

       want to specify the compile, you can set the CC environment

       variable prior to running CMake.

    $ cmake ../curl

    $ make

    3. Install to default location:

    $ make install

    (The teste suit does not work with the cmake build)

ccmake

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