add getCompiler and getLinker methods, to abstract from XSD.
add calc_source_md5 as it's more convenient especially for embedded
targets to add -DPLC_MD5="something" option at compile time than
to mess with editing binary.
add some more helper methods

make run Beremiz and PLCOpen Editor, if full path contain non-lating
characters

There was a problem in About dialog and in project properites tab and
probably in my other places, when str is automatically converted to
unicode string using ascii.
This patch converts str to unicode using proper encoding at the very beggining.

README.md edited online with Bitbucket