* MAKE - improvement
- specify SDK file for each target pair on linux and macosx
- verify checksum before unpacking downloaded file (curl ignores server
certificate)
- infer ARM_SDK_DIR from SDK file name
- detect installed SDK, checking that it is newer than downloaded
file (.installed file in SDK dir)
- fix unzip on windows (doubly nested SDK directory was created)
* MAKE - fix .zip handling
* MAKE - unintended space on windows
When trying to build firmware with current directory in PATH environment
it scans for make command and generates "Permission denied" error in
case if current directory in PATH precedes /usr/bin/ directory.In my
case it was caused by incorrect pyenv init script.
Rename make folder to avoid errors like this.
