Update README

Some time without a commit now - this is just a few paragraphs for the
README to get the basic idea written down.

depot/README outlines a thought I had about using conventional DMBS in the
depot routines. I think we need to implement a custom one for best
performance.

I'm going to push all the local changes I have made over the time now in
discrete commits.
Begin read_config API

The read_config API is there to provide a simple parser for configuration
files for the servers. Planned are only integers and strings. I hope that
the documentation can be left as-is, i.e. no more features are required.
Write some hypothetical P functions

The repository got a vim template and vim syntax highlighting support for P
source files. Note that nothing is done in the actual code. These are just
tests to get a grasp of what the language will need. The asm-gen.c and
preproc.c files are empty, IIRC.

p-lang/primes.P contains _lots_ of comments on features. I will tidy these
up and then make a clear plan once the network protocol is on its way.
Interesting how a primality test in the collective could look like, though!

The p-lang/goldbach.P chronologically first and in all rawness imposed the
need on me to make tuples a native data type of P. Most thoughts, however,
are to be found in the big primes.P file, not all of which are compatible or
listed in chronological order.
Small fixes and enhancements in Makefile.aesthetic

Quote a double quote in the par invocation. How could it have worked before?

The pipe symbol and the space are now also protective characters to par.
This is to let diagrams and lists - mainly in PROTOCOL - be untouched.
Begin working on native tuple support

The routines in lib/tuple.c are meant for the P language. There are still
some issues left to be solved like if nested tuples should be allowed or how
this concept could be replaced, should there be a distinction about easy and
complex native data types, etc..

Since the P language indirectly accesses the depot DBMS routines using
tuples, it would be good if the code can equivalently well be used by the
DBMS. We shall see this later. The get_tuple_hash() function is something we
would really like to implement then. Not to mention that it would be so much
faster (if we stay on the local machine) if the backing structure would not
need any conversion between what is manipulated from P and seen by the DMBS.

As said in the depot/README, we will need a good binary search tree for
SHA-1 (or one of the bigger SHA-2 algorithms) hashes. I hope that creating
include/btree.h reminds me of that betimes.
Progress on PROTOCOL

Another very drafty and incomplete version of the Unicomplex Protocol. There
are still many things to say, ambiguities to clarify and confusions to
redeem. I'll work on this primarily now.