Changes 1.2.0
 * place version macros into the C so that they are private (thanks to Jason Cooper)
 * add license files (thanks to Jason Cooper)
 * change drng_chacha20_versionstring to return the snprintf error (thanks to Jason Cooper)

Changes 1.1.0
 * fix invocation of getrandom syscall
 * remove debug printf
 * use private name space for version macros
 * add API calls to obtain version of implementation

Changes 1.0.0
 * Initial version
