make: clean up, test .NOPATH

Trim down the comments in the archive module, as they mainly repeated
the code. Trim down the binary code size in the archive module, as it
is rarely used.

In Var_Parse, delay two variable assignments until they are actually
needed.

make(1): add dummies for fine-grained tests, one per single feature

The test names have been derived from the current manual page.

All these tests are dummies right now, and the code from the existing
tests will be moved into the new tests step by step.

This is done to prevent modmisc, escape, varmod-edge and varmisc from
growing without any bounds, and to reduce the side-effects of one test
to the others.