MikroC compiler support and minor features

Hello! Thanks for sharing your code.

This request includes a port to MikroC compiler (for ARM).

In one hand, this patch includes macros that hopefully make it easier to port ctest to new platforms. I think ctest is a good choice for embedded: it's quite easy to port it to because it is only one header; and it is still have useful features.

In other hand, this patch includes several ugly workarounds and #ifdefs related to MikroC issues.

Please see modified version of README and commit message for details.

Two last commits just add some minor features.