This patch contains several changes according to ODFF

(1) Introduce the GAMMA function

I put the GAMMA function to the group "Statistical functions", although it is in
the "Mathematical" group in chapter 6.15 in ODFF spec, because the GAMMALN
function is in "Statistic" too.

The domain of the GAMMA function contains negative values. The ODFF draft spec
is not adapted yet.

(2) Introduce CHISQDIST
In contrast to CHIDIST (now LEGACY.CHIDIST) it gives the left tail probability,
same as other distributions do. In addition it has an optional parameter to
calculate the density function.

(3) Introduce CHISQINV
I use the same way as the other inverse distribution functions are computed.

(4) Adapt the "cumulative" parameter of the GAMMADIST function to be logical and
optional.

(5) Adapt the domain of CHIDIST to allow negativ x, see ODFF 6.17.10.

(6) Remove the constraint "degrees of freedom < 1.0E5" from CHIDIST and CHIINV
because they are no longer needed with the new implementation in issue 90703.


Please notice, that the ODFF draft spec is wrong in the third parameter of
GAMMADIST and GAMMAINV. OOo, Excel, and Gnumeric use the third parameter 'beta'
in the way, that mean=alpha•beta, but ODFF draft spec uses the third parameter
'lambda' in the way that mean=alpha/lambda. The application help must explain,
which use of the parameter OOo has, because the commom usage of the parameter
differs between countries.

Unfortunately the identifier GAMMAINV is already used for the inverse of the
Gamma-distribution. It can likely be confused to be the inverse of the Gamma
function. A comment in the application help is necessary.

The patches are zipped to one file. The patches are made against this versions,
which is m30 and cws odff05:
compiler.hrc    Revision 1.20
opcode.hxx      Revision 1.23
compiler.src    Revision 1.59
scfuncs.hrc     Revision 1.14
scfuncs.src     Revision 1.95
hidother.src    Revision 1.29
interpr.hxx     Revision 1.35
interpr4.cxx    Revision 1.57.98.2
interpr3.cxx    Revision 1.25