Remove Rip::Parser#do_nothing placeholder
Rename several methods for clarity
All handle_* methods need to follow the same interface
Accurately specify where tokens should be found
Rename local variable
Extract #parse_next_token from #parse_tree and push nodes onto a stack
Implement Rip::Parser#handle_equals for assignment
Parse properties
General code cleanup
Implement Rip::Location#add_{character,line}
Refactor tests
Extract some lets in tests
Remove superfluous Rip::ListScanner#reset!
Move/refactor Rip::Keywords into Rip::Nodes::Keyword
Organize require statements in lib/rip/parser.rb
Promote parser's stack to first-class citizenship
Add Rip::Nodes::{Block,Lambda}
Move Rip::Parser#parse{_tree,}
Implement Rip::ListScanner#current
Add Rip::ListScanner#{remember,recall}_position