fixed typo
Minor change in comment header.
minor change
binaries for ditribution package are now statically linked.
minor documentation changes.
updated readme.txt

Added several notes informing users that compilation of the model is
optional.
Updated versions with which compilation has been tested successfully
(gcc, clang).
Added note on required packages for cross-compilation.
Wrote changelog for version 1.4 Final.

Note: i chose to finalize version 1.4 without including the rkf45
fix (issue #34) because several people have been doing a lot of work
with v1.4 Beta. Including a fix for #34 would likely change their results,
resulting in unnecessary work and lack of result reproduceability.
This is alse the reason why i changed the version tag from "beta" to
"final".
added a note on the versioning scheme