Code cleanup for pull request
Templatization of the blas_lapack calls for Cholesky update completed
Author name fixed
Merge pull request #15 from Ommac/origin/recursiveCholesky

added recursive cholesky task
adding train-test functionality
guide update
options update
test update
guide update
GurlsOptions updated
guide-train-test update
Merge pull request #16 from alessandro-rudi/master

Updated gurls matlab:
- opt is now a class
- added train and test functionalities
- added guide-train-test manual
Fixed to gmat2D

added constness to min and max method
added const version of operator()
fixed a bug in operator-
minor change to traintest.hpp  / added utility isLabel

default traintest nholdouts increased
added isLabel utility function to determine if a given matrix is in an
accepted label form
major changes to gurls++ internal structure + minor fixes

- all tasks are now derived from class Task<T>
- added class OptTask
- optTaskSequence now also accepts OptTask objects as input
- factory system changed, it is now possible to register factories at
run-time (see manual for detailed usage)
- manuals updated
- macroavg now computes mean per-class accuracy even if labels are
passed in a single column (binary classification)
- splitho now balances the splits if labels are passed in a single
column
- added totalavg perf measure to compute total classification accuracy
(class independent, previously, the standard behaviour of macroavg for
one column binary classification)
bug update
gurls_helloworld update
updated guide for train test functions
test updated