linear_congruential_engine : fix typo
Merge pull request #171 from faithandbrave/fix_typo_lcg

[rand.eng.lcong] linear_congruential_engine : fix typos

Reported by Akira Takahashi
ranlux48 : fix typo
Merge pull request #173 from faithandbrave/fix_typo_ranlux48

[rand.predef] Fix typo "@" -> ";" in ranlux48 definition. Thanks to Akira Takahashi!
[pairs.pair] Fix typo to refer to member functions plural.

Fixes #175
Reported by Stephan T. Lavavej.
[string::assign] Add missing paragraph number and remove duplicate.

Fixes #176
Reported by Stephan T. Lavavej.
Add a simple tool (written in C++11) to print out section numbers.
Small improvements to sections.cpp.
tools/sections: Ignore commented out section commands

This avoids the tool recognizing lines like:

%gram: \rSec1[gram.over]{Overloading}

as the start of a new section.