- rely on OPENOCD_SCRIPTS variable in all cases, remove -s flags
- replace installation section with a reference to the Getting Started
guides
- add Windows-specific commands in a few cases
1. Moved get-started files, 7 documents in total, from get-started-cmake folder to hw-reference folder;
2. Deleted get-started files, 7 documents in total, in get-started folder;
3. Updated links in get-started-cmake/index.rst and in get-started/index.rst;
4. Modified descriptions for build system in these files.
