add chris updated traverse
fix merge conflicts
Removed old syntax examples
Added comment banners at top of files
Modified svelLex.py to tokenize input file

Used to only tokenize user input; can now tokenize input file with call:
```python svelLex.py <path_to_input_file>```
Fixed shift/reduce conflict and added file parsing

Like svelLex, can now parse input file with call:
```python svelYacc.py <path_to_input_file>
allow variable declaration in parser
parser: allow print of an expression
parser: allow print of an expression
begin implementing type/value checking
Merge branch 'master' of https://github.com/svelTest/svelTest into treewalk

Conflicts:
	lib/svelTraverse.py
	lib/svelYacc.py
traverse: update assignment_helper
traverse: error msg formatter
Merge branch 'treewalk' of https://github.com/emilyhsia/svelTest into treewalk

Conflicts:
	lib/svelTraverse.py
Merge branch 'master' of https://github.com/svelTest/svelTest into treewalk
fix spacing/indentation errors
fix format_err_msg bug
merge
implement _recognize_type_helper to determine the type of a primary expr
begin returning types: primary_expr