Implements Kahan's versions of elementary complex functions…

…paying particular attention to behavior near branch cuts.

Functions: sqrt, ^, log, asin, acos, atan, tanh, asinh, acosh, atanh
Includes also the ssqs to compute the mod-squared of a complex number scaled by a power of 2 to avoid overflow/underflow
Issues
- The ^ function fails tests so is disabled for now.
- The log function works only for `Complex{FloatingPoint}`. Explicitly casting `{T<:Integer}Complex{T}` to floating-point `Complex` causes tests to fail.

Ref: [Branch cuts for complex elementary functions](http://people.freebsd.org/~das/kahan86branch.pdf)
Correctly detects for both underflow and overflow in ssqs
Fixes type error in log
Corrects underflow check
Adds edge cases for all except atanh, atan
Reorders tests
Fix markdown link syntax
doc: ceil, floor, round etc. return the same type as their argument.
Fixes #2992; Reorders #bracket rule and cleans up transpose tick matching
Merge pull request #2996 from karbarcca/patch-2

Fixes #2992; Reorders #bracket rule and cleans up transpose tick matching
Revert "Fixes #2992; Reorders #bracket rule and cleans up transpose tick matching"

This reverts commit f200340d42b48e6080fde95a434ff6a366fd49e7.
Changed top-level bracket rule to not consume when transpose tick is present; Fixes #2992

This seems to solve the transpose tick problem while also not introducing the syntax-blocking (like the last fix). Can others confirm before we merge this time?
Merge pull request #2999 from karbarcca/patch-3

Changed top-level bracket rule to not consume when transpose tick is present
fix a type intersection bug, closes #2997

this also exposes 2 new method ambiguities (in scale!)
Merge branch 'master' of github.com:JuliaLang/julia
WIP on FDWatcher
poll_fd and a test for the same
Fix an assertion failure caused by double close on exit
File Monitoring Stuff
Implement @amitmurthy's suggestions. Fixes #2895
run gui editors using spawn instead of run.
add kate support, should fix #2994
Merge branch 'master' of github.com:JuliaLang/julia