update doc building and badges

Author: jlapeyre

README.md

@@ -3,6 +3,7 @@
 *Numerical inverse Laplace transform*
 
 [![](https://img.shields.io/badge/docs-latest-blue.svg)](https://jlapeyre.github.io/InverseLaplace.jl/latest)
+[![](https://img.shields.io/badge/docs-stable-blue.svg)](https://jlapeyre.github.io/InverseLaplace.jl/stable)
 Linux, OSX: [![Build Status](https://travis-ci.org/jlapeyre/InverseLaplace.jl.svg)](https://travis-ci.org/jlapeyre/InverseLaplace.jl)   Windows: [![Build Status](https://ci.appveyor.com/api/projects/status/github/jlapeyre/InverseLaplace.jl?branch=master&svg=true)](https://ci.appveyor.com/project/jlapeyre/inverselaplace-jl)      
 [![Coverage Status](https://coveralls.io/repos/github/jlapeyre/InverseLaplace.jl/badge.svg?branch=master)](https://coveralls.io/github/jlapeyre/InverseLaplace.jl?branch=master)
 [![codecov](https://codecov.io/gh/jlapeyre/InverseLaplace.jl/branch/master/graph/badge.svg)](https://codecov.io/gh/jlapeyre/InverseLaplace.jl)

docs/make.jl

@@ -12,7 +12,8 @@ makedocs(
 deploydocs(
     repo = "github.com/jlapeyre/InverseLaplace.jl.git",
     target = "build",
-    julia  = "0.6",
+    julia  = "0.7",
+    osname = "linux",
     deps = nothing,
     make = nothing
 )

src/weeks.jl

@@ -29,7 +29,7 @@ _set_coefficients(w::Weeks) = (w.coefficients = _get_coefficients(w))
 const weeks_default_num_terms = 64
 
 """
-   w::Weeks = Weeks(func::Function, Nterms::Integer=64, sigma=1.0, b=1.0; datatype=Float64)
+   w::Weeks{datatype} = Weeks(func::Function, Nterms::Integer=64, sigma=1.0, b=1.0; datatype=Float64)
 
 Return `w`, which estimates the inverse Laplace transform of `func` with
 the Weeks algorithm. `w(t)` evaluates the transform at `t`. The accuracy depends on the choice
@@ -163,7 +163,7 @@ function optimize(w::WeeksErr, t)
 end
 
 """
-   w::WeeksErr = WeeksErr(func::Function, Nterms::Integer=64, sigma=1.0, b=1.0; datatype=Float64)
+   w::WeeksErr{datatype} = WeeksErr(func::Function, Nterms::Integer=64, sigma=1.0, b=1.0; datatype=Float64)
 
 Return `w`, which estimates the inverse Laplace transform of `func` via the Weeks algorithm.
 `w(t)` returns a tuple containing the inverse transform at `t` and an error estimate. The accuracy of the