track back->forward conversions in a bitmask
wip on adding tests at higher level, some not right
fix multiple sequential slashes
path decanonicalization when building command
remove CanonicalizePath overloads, test for toplevel behaviour
fix order of args to CanonicalizePath
assert no slashes in default GetNode
improve test
non-win compilation
make all GetNode explicit, add DepsLog canonicalize test
initialize slash_bits on non-win
fix CanonicalizePath going past StringPiece length + test
no need to Decanonicalize on non-Windows
save slash_bits in depslog
no need to save slash_bits, add comment
fix not respecting length
properly guard against slash_bits overflow
Merge pull request #848 from sgraham/canon-maintain

Maintain bitvector of original slashes from manifest when canonicalizing