makesingular{.debug}: pass args through to "make"

This makes it possible to write "./makesingular -j8" to use all your CPUs.
PackageInfo.g: Update Max N's address; update maintainer flags

Hans, Max N, Oleksandr are not currently "maintainers" (in the sense
that bug reports etc. should not be sent to them).
Overhaul printing of Singular objects
Extend support for  matrix[[i,j]] syntax

With the GAP branch sl/list-extensions, this now allows the following
operations with singular matrices, including (big)intmats:
* mat[[i,j]] := val;
* IsBound(mat[[i,j]]);
* Unbind(mat[[i,j]]);  # always fails / errors out
Various minor tweaks, cleanups, code formatting, ...
Makefile.am: use -R in SingularInterface_la_LDFLAGS

This ensures our kernel extension will work even if the Singular .la
files are not installed.
Version 2014.09.23
Makefile.am: don't display pointless success banner
Makefile.am: add 'doc' target
Reference and require Singular >= 4.0.1
Do not install certain gap kernel handler funcs

Specifically, do not touch
 IsbbListFuncs
 UnbbListFuncs
 AssbListFuncs
They are not really being used by GAP for now, and they
are likely to be removed again in the future. Our
kernel ext is probably the only piece of code using
them right now, outside of the GAP kernel.
doc: allow building the manual when package is not in GAP root dir

By adding
  SetPackagePath("SingularInterface", ".");
to makedoc.g, the script becomes more robust and works correctly
even if SingularInterface is not currently in a pkg dir visible
to GAP.
Change version to 0.6.

Closes #21.
Adapt gentable to recent Singular changes

Fixes #22.
Singular team silently replaced the 4.0.1 tarball