Port of a very trivial Matrix implementation of size 1x1. While trivial,
this case does occur relatively often when computing derivative of a one
dimensional CRS (e.g. the vertical or time axis).

2x2, 3x3 and 4x4 cases will be commited next, then a general case based
on JAMA for all other sizes (including non-square matrices).


git-svn-id: https://svn.apache.org/repos/asf/sis/branches/JDK7@1521547 13f79535-47bb-0310-9956-ffa450edef68