Added some CMake README.md tweaks (#2870)
Added some CMake README.md tweaks (#2870)

* Added some CMake README.md tweaks

* better layout, use less confusing metasyntactic variables for configure example

Co-authored-by: kyle <3c25b01657254677d3e1a8fd1f0742c5d489bd39@awesomeguy.co.za>
or-tools/or-tools,or-tools/or-tools,google/or-tools,google/or-tools,or-tools/or-tools,google/or-tools,or-tools/or-tools,or-tools/or-tools,or-tools/or-tools,google/or-tools,google/or-tools,google/or-tools