Revert "put include guards on boost/function"

This reverts commit 8f0fe88635c0a06969b7f49b13e4fb74b066b317.
revert and fixup boost/function.hpp external include guards
Merge branch 'fixup_external_incl_guards'
fixup camel case names UnitPtr, UnitConstPtr

This commit created using sed, in directory src/:

$ find . -type f -exec sed -i 's/UnitPtr/unit_ptr/g' {} +
$ find . -type f -exec sed -i 's/UnitConstPtr/unit_const_ptr/g' {} +

and inspecting the results.
fixup a memory leak in actions/undo.cpp

This fixes up commit
https://github.com/wesnoth/wesnoth/commit/64e69cd6#diff-f925ac8cf45da1ab4547b483379d9b75R253

Issue spotted by coverity static analysis tool.
fixup silenced warnings in ai/actions.cpp

Better to demote them to a lower channel rather than disable
completely.
fix a comment that contained an invalid char.
fixup potential null dereference in server code

If a client submitted a bad message it would cause the server to
crash.

Issue found by coverity.
fixup windows compilation
Merge branch 'fixup_server_null_deref'
Fix file encoding.

The issue was spotted by iceiceice.
Remove a template specifier.

Instanciating std::make_pair normally shouldn't be used with template
specifiers. In this case it broke compilation for C++11.
Select the proper overload for boost::bind.

In C++11 there are two viable overload of the function. Specify the
proper overload to avoid a compilation error.
Fix compilation with C++11.
Allow old-style casts for a file.

It uses some external macros that add the old style casts.
Disable a useless cast in CMakeLists.txt.

The uselessness of the cast depends on the platform, so silence the
warning.
add check utf8 bash script, for data and src dirs
test what happens with check_utf8.sh on travis
add "moreutils" lib to travis script, for utf8 check
add time checks for package installation commands to travis.yml