Include cc/c++ in compilers

[jakirkham]

It's very common for builds to use cc or c++ as the executables to call compilers by. Would be very useful to have these executables included in the compilers so that they work smoothly in these cases.

[minrk]

It would also be great for gcc/gxx to have their normal executable names as well

[jjhelmus]

Having the compiler activation alias cc, c++, gcc or gxx has the potential to shadow the system compilers with the same name. I can imagine this would come as a surprise to many users.

Perhaps an alternative would be to only activate these aliases inside conda-build environments. This would solve problems where various build tool try to call the compiler by these names but would not shadow the system compilers in user space.

@mingwandroid do you have any thoughts on this topic?