fixed up some things
Merge pull request #10 from dmb2168/chris_kira_semantic_analysis

Chris & Kira Full Compiler Baseline Working
fixed some pointer manipulations. UNTESTED
Merge branch 'master' of github.com:dmb2168/PLT
compiles! needs testing
Fixed semantic checking issues. dfs.lrx passes semantic analysis now
True and false defined in lrxlib
polymorhpism fixes
initializing trees and printing them now functions properly.
lrxlib:
fixed merge conflict.
initializing trees and printing them done.
added test C program for library
Added preliminary stack example
Added stack preliminary example with workaround for semantic checking issue
Added some comments to stack.lrx
moved lrx_test.c removed todo on stack.lrx
removed bad ast comments from example lrx progs
new lrxlib interface.
-deconstructor is likely to change
-need to add functions to deal with dereferencing and mutating actual data elements
-need to overload subtree function to provide function that doesn't create a new subtree and returns pointer to existing one instead
Merge branch 'master' of github.com:dmb2168/PLT
Added a array.lrx, which does array operations
Merge branch 'master' of https://github.com/dmb2168/PLT