Moved float str buffer constants to the strconv module
pre-rebase commit
Switched over a bunch of splitting funktions to non-allocating iterators
Isolated bug, static vector seems to behave differently than fixed sized one
Fixed all use sites and tests
Added missing lifetime annotations, doc and whitespace cleanups
Added more missing lifetime annotations
auto merge of #5555 : Kimundi/rust/str-dealloc-3, r=catamorphism

- Most functions that used to return `~[~str]` for a list of substrings got turned into iterators over `&str` slices
- Some cleanup of apis, docs and code layout
Remove unused imports throughout
syntax: Removing uses of HashMap
doc: Remove mentions of oldmap::HashMap
rustc: Remove uses of oldmap::HashMap
rustc: Purge of HashMap, fixing segfaulting cases

Various FIXME comments added around to denote copies which when removed cause
the compiler to segfault at some point before stage2. None of these copies
should even be necessary.
test: Remove uses of oldmap::HashMap
Move ast_map::map to LinearMap
std: Remove the oldmap module