Merged changes from Trunk: mostly platform and compiler specific workarounds.

[SVN r51457]
Set last merged revision no.

[SVN r51458]
Fixed a mistake in error case explanation.

[SVN r51554]
added laplace distribution

[SVN r55664]
uadded laplace distribution


[SVN r55665]
added laplace distribution

[SVN r55680]
added laplace distribution

[SVN r55681]
added laplace distribution

[SVN r55682]
Corrected mistakes as reported by 

> On Behalf Of Ralf M.
> Sent: Monday, August 31, 2009 11:56 PM
> To: boost-users@lists.boost.org
> Subject: [Boost-users] [Math] Bug in example code / doc (Binomial Distr.)



[SVN r56273]
Added desktop icon to setup distex

[SVN r56371]
Merged changes from Trunk.

[SVN r56667]
added missing newline at end of file.

Compiles OK with \Za disable SM extensions and NO warnings.

[SVN r57459]