add nsis* to .gitignore
add mxe to .gitignore
cmake: fix finding boost components (MXE)

Boost 1.57
MXE c85476ccd45ada1d593cc5

Cmake doesn't find *-mt-s*.a boost libraries without
set(Boost_USE_STATIC_LIBS ON)
windows: use LuaJIT instead of Lua
windows: build 32-bit and 64-bit versions
gui: fix rare error message

Error message:
> The error occured.
>
> Description for developers:
>
> gui/AlignmentModel.cpp:352: bool AlignmentModel::is_gene_start_stop(npge::Fragment*, int) const: Assertation `genes_s2f_' failed. Error message `0'.

Reason: some object was not given to AlignmentModel
(object VectorFc genes_s2f).
Lua: helper function while_changing

while_changing() creates a processor, trying any processors
using TrySmth one after another, while the resulting
blockset is changing.

Use this function for processors building pangenome.