Merge pull request #148 from ckormanyos/update_docs

Update docs

README.md

@@ -80,12 +80,12 @@ The commands are as shown below, where you need to specialize `--boost`, `--my_c
 
 ```sh
 cd mandlebrot
-./build_all --boost=../boost-root --my_cc=g++ --stdcc=c++20
+./build_all.sh --boost=../boost-root --my_cc=g++ --stdcc=c++20
 mkdir -p images/tmp
 ./test_mandelbrot.exe
 ```
 
-The script [`build_all.sh`](./build_all.sh) is used to:
+In summary, the script [`build_all.sh`](./build_all.sh) is used to:
   - Build the JPEG, ZLIB and PNG libraries with GNUmake.
   - Compile and link [`test_mandelbrot.cpp`](https://github.com/ckormanyos/mandelbrot/blob/main/test/test_mandelbrot.cpp) to obtain the test program `test_mandelbrot.exe`.
   - Execute the test program via `./test_mandelbrot.exe`. The resulting JPEG and PNG images will be placed as a temporary file in the `images/tmp` folder.
@@ -98,6 +98,8 @@ You may need to supply your system's (or your desired local) path to boost.
 
 Make the needed output image directory and run `test_mandelbrot.exe`.
 
+### Optionally Use `gmp_float`
+
 To optionally use `gmp_float`, the [GMP](https://gmplib.org) big-number backend,
 instead of `cpp_dec_float`, where both backends are from
 [`Boost.Multiprecision`](https://www.boost.org/doc/libs/1_86_0/libs/multiprecision/doc/html/index.html),