Fix find() when called with function and non-StridedArray

The previous code expected testfun to be vectorized, which does not match
the behavior of other methods, nor the documentation. Especially visible
when passing a sparse matrix. Always return an Array rather than an object
similar to the input, because it makes no sense to return a sparse vector.
Remove the method matching any object so that an error is raised rather
than returning incorrect results on non-AbstractArray (e.g. Set).
Remove defunct link.
Update base.rst
Update helpdb.jl
Merge pull request #8376 from apeyser/master

 Suggestion: add to whos() documentation that it only displays exported variables #8375
add DATAROOTDIR to build_h.jl, use it in Base.runtests()
deprecate randbool! and add rand(Bool). fixes #8377
Merge pull request #8323 from nalimilan/find

Fix find() when called with function and non-StridedArray
added built-in exception UndefVarError to manual
Merge pull request #8386 from davidssmith/man

added built-in exception UndefVarError to manual
close #8304, tweak openblas build troubleshooting

this is a bit redundant, but it definitely belongs under the category of openblas build failure
Use a larger stack for PCRE's JIT. Fixes #8278.
Bump libosxunwind to 0.0.1. (RC3 was marked as release).
move default setting of prefix to Make.inc,

change SYSCONFDIR and DATAROOTDIR to be relative paths
Stylistic change

See https://github.com/JuliaLang/julia/pull/8323#discussion_r17609618
fix eigfact doc
splice!: allow replacement argument to be anything enumerable.

This is a good example of scalars being iterable being a good thing.

cc: @carlobaldassi – splice! for BitArrays should also be generalized
but I was finding it tricky to figure out the best way to do so.
Merge pull request #8391 from rfourquet/docs-linalg

fix eigfact doc
Merge pull request #8379 from JuliaLang/tk/datarootdir

add DATAROOTDIR to build_h.jl, use it in Base.runtests()
Fix Triangular methods for the case where the diagonal is unity. Add some tests and split the triangular tests into their own test file.