Documentation on *make* describing the interfaces between bazel and Makefile

By interfaces, I mean the variables input to the make commands, how they are translated from the rule args (eg. INSTALLDIR), make commands output directory structure expected by bazel.

Roughly, this information is important for someone who is getting started with bazel, and look at the output and variable used for the existing makefile, figure out how to adjust Makefile and variable setup, to work with Basel.

The experience today is considerably and unnecessarily hard to people new to bazel. As often simple issues become major task of investigation because users were not aware of certain setups and expectations of bazel on the Makefile and make commands.

Such documentation will do huge help to new adopters without significant amount of investment as these knowledge is already very well known to the maintainer.

Unfortunately, I am new to bazel and cannot recall help with this.

Start by locating the existing documentation, Makefile, make commands, and Bazel rule definitions that expose the interfaces described in the issue. Document the input variables, their translation from rule arguments, and the output directory structure expected by Bazel; done means a new Bazel user can understand and adjust the Makefile setup.

Written by the indexing model from the issue text.