new plugin providing a symbolic annotation to constants. currently not translated to prob (working on it)
add symbolic plugin to gradle
add the symbolic pragma to the translator
removed content from symbolic pragma as it has no parameters
change attribute type of symbolic attribute from string to boolean in the translator
do not set the symbolic static checker on machines, only on constants = only in contexts
change "concrete" to "not symbolic"
Merge branch 'feature/symbolic_pragma' into develop