MAHOUT-1346: (D)-SPCA and other additions and fixes.

Squashed commit of the following:

commit 1ed6267a3cc550d1d648346fca7e152c63909667
Merge: 95da094 c0260b5
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Mon Mar 17 11:38:33 2014 -0700

    Merge branch 'trunk' into dev-1.0-spark

commit 95da094a38d7fbbd654e95bbfb5723c5e1e48c55
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Mon Mar 17 11:24:28 2014 -0700

    D-SPCA fixes. test is passing (in-core and out-of-core tests give the same result). However, the test seems to be still rank-deficient (rank=20 instead of desired 100). Not sure why -- the Cholesky seems to be too sensitive.

commit c907be0f9b35436cf623e1a92941f924382b531d
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Mon Mar 17 00:10:05 2014 -0700

    Fixes for D-SPCA: q=0 works, q>0 still doesn't

commit 0e24fe88cbbae2db57c06b4d85f5df1b5a2925e5
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sun Mar 16 18:16:27 2014 -0700

    added test for colSums, colMeans

commit 1012d65ba360cfe944f2f559cf032c7546e19072
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sun Mar 16 18:08:25 2014 -0700

    D-SPCA WIP. Test is not yet working with -q0

commit 5560f1e928380280b23dbd35efec39b8566eb1a3
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sun Mar 9 18:12:03 2014 -0700

    Fixng random gen in SPCA test codegen

commit 740cac1eec6a4e1bf256066d86b7b5681f88bd4c
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sun Mar 9 18:08:30 2014 -0700

    removing check for rank deficiency (so pca can complete). User can check the results for that if needed.
    Adding in-core s-pca test.

commit f1abfe430987b60a62a0e65cf234ebdc40135275
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sun Mar 9 16:19:32 2014 -0700

    perhaps a better ssvd test assertion

commit e26596fd6cecb74055c38d838a8b02e9698b17f8
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sat Mar 8 22:01:58 2014 -0800

    first write-up of in-core stochastic PCA

commit eb3bf98d6abcd8f480e892c74bd7f61b32b33bdf
Author: Dmitriy Lyubimov <dlyubimov@apache.org>
Date:   Sat Mar 8 20:35:24 2014 -0800

    rowsums, colsums, rowmeans, colmeans for in-core + tests

git-svn-id: https://svn.apache.org/repos/asf/mahout/trunk@1578527 13f79535-47bb-0310-9956-ffa450edef68