Add support for code coverage on Solaris

[saprykin]

Solaris has its own code coverage tool named tcov.

About using tcov: Analyzing Program Performance with Sun WorkShop.

About -xprofile option for Oracle/Sun compiler: Oracle docs.

I have also found some useful information about Oracle/Sun compiler versions: old versions and newer versions. We need it because there two ways to enable code coverage, and according to some threads a new way was supported at least since SunPro C 4.x version.

During library configuration we should select one of the code coverage ways.