drop LTS support:

- first, it's really dull to keep compatibility with LTS
- and now we want to use `Base.@kwdef` for creating types with 
supertypes, and LTS can't have that for reasons

.travis.yml

@@ -2,7 +2,6 @@ language: julia
 
 julia:
   - 1     # current stable
-  - 1.0   # lts
   - nightly
 
 script:

Project.toml

@@ -23,7 +23,7 @@ Mustache = "0.4.1, 0.5, 1"
 Plots = "0.28, 0.29, 1.0"
 Requires = "1.0"
 YAML = "0.3, 0.4"
-julia = "1"
+julia = "1.1"
 
 [extras]
 Cairo = "159f3aea-2a34-519c-b102-8c37f9878175"

src/Weave.jl

@@ -29,10 +29,6 @@ function __init__()
 end
 
 # utilitity functions
-@static @isdefined(isnothing) || begin
-    isnothing(::Any) = false
-    isnothing(::Nothing) = true
-end
 take2string!(io) = String(take!(io))
 
 """