beremiz

file isExecutable
fix issue with sequence of multiple whitespaces in makefile command
line from project configuration

for every additional whitespace '""' was inserted in result command line.
<xsd:attribute name="Command" type="xsd:string" use="optional" default="make -C %(buildpath)s all BEREMIZSRC=%(src)s BEREMIZCFLAGS=%(cflags)s MD5=%(md5)s USE_BEREMIZ=1 FROM_BEREMIZ=1"/>