Add libunwind patch from Pyston
beginswith, endswith accept Chars
Expand macro documentation

These changes are based somewhat on the [discussion on the julia-users list](https://groups.google.com/d/msg/julia-users/YTZM3Biy-rM/m0orpSjQ8RIJ) and somewhat on my own stumbling points as I was learning how macros worked.

Here's the motivation behind these changes:

* Stress that macros *return* an expression to be evaluated, and hopefully make it look like they're less magical to newcomers. Make `return` explicit in the examples, so it looks less like textual substitution and more like a mapping from exprs to an expr.
* Provide an example where the macro is more than just return an expression. The changes to `@assert` since the original documentation was written make this very natural without needing to contrive another example.
* Use function such as `macroexpand` and `dump` in the examples to help make things more concrete and give users tools to play with.
* Make the hygiene section introduction a bit more clear, with an emphasis that the only thing it needs to worry about is the returned expression.

I think this should help folks 'get' macros a bit quicker. I hope.
Update linalg.rst

Complemented linreg() documentation
Loosen types on mmap on unix

In particular make it work for isa(fd,RawFD) and offset any integer type (there is a lot of precedent for allowing any Integer Rather than just FileOffset. In particular most of the io.jl methods do this).
Merge remote-tracking branch 'origin/kf/mmap'
Make RawFD a noop for passed in RawFD

this can happen in the Windows mmap code and it would be much nicer if it
just worked.
parse sqrt symbol (√) as a unary operator
Fix clean-arpack as well
Revert "Manual update"

This reverts commit a8dbe6bd5219285681870a530d4f449f89b7b6c8.
Changed .julia -> .julia/v0.3
Merge pull request #6806 from JuliaLang/kms/fix_docs

Fix #6575
Corrected examples on linreg function

Removed the prompt and semicolons
Fix promotion for generic inverse. Add convert methods for Triangular.
Mapping over [] returns []. Fixes #6719

map(f, []) now returns [] (an Array{None,1}).

Running [][map(x -> x, [])] no longer fails due to bounds checking errors.
This was happening because [] is of type Array{None, 1}, whereas ie
map(int, []) is of type Array{Any, 1}.
Use vecnorm in norm(Matrix) when first dimension has size one.
Fix some issues related to eigvals

- Pass arguments to eigvals to eigvals!, so that eigvals(A, irange)
  and eigvals(A, vl, vu) work as described in the docs
- Restrict eigvals!/eigfact! to real symmetric/Hermitian or complex
  Hermitian matrices. Previously we allowed these methods to be called
  on complex symmetric matrices, which did not give correct results.
Introduce RealHermSymComplexHerm typealias and use where applicable
Make Travis status image use master branch for new packages
update openlibm. closes #6777