Numerous yarn warnings when creating a new application

[duffn]

Steps to Reproduce the Problem

1. Install buffalo
2. cd $GOPATH/github.com/$USER
3. buffalo new warningapp

Expected Behavior

The app is created with no yarn warnings.

Actual Behavior

The app is created with numerous yarn warnings.

         run  yarn install --no-progress --save
yarn install v1.9.4
info No lockfile found.
[1/4] 🔍  Resolving packages...
warning babel-preset-env > [email protected]: Browserslist 2 could fail on reading Browserslist >3.0 config used in other tools.
warning css-loader > cssnano > autoprefixer > [email protected]: Browserslist 2 could fail on reading Browserslist >3.0 config used in other tools.
warning css-loader > cssnano > postcss-merge-rules > [email protected]: Browserslist 2 could fail on reading Browserslist >3.0 config used in other tools.
warning css-loader > cssnano > postcss-merge-rules > caniuse-api > [email protected]: Browserslist 2 could fail on reading Browserslist >3.0 config used in other tools.
warning node-sass > request > hawk > [email protected]: The major version is no longer supported. Please update to 4.x or newer
warning node-sass > request > hawk > boom > [email protected]: The major version is no longer supported. Please update to 4.x or newer
warning node-sass > request > hawk > sntp > [email protected]: The major version is no longer supported. Please update to 4.x or newer
warning webpack-cli > jscodeshift > [email protected]: 🙌  Thanks for using Babel: we recommend using babel-preset-env now: please read babeljs.io/env to update!
warning webpack-cli > webpack-addons > jscodeshift > [email protected]: 🙌  Thanks for using Babel: we recommend using babel-preset-env now: please read babeljs.io/env to update!
warning webpack-cli > jscodeshift > [email protected]: Package no longer supported. Contact [email protected] for more info.
warning webpack-cli > webpack-addons > jscodeshift > [email protected]: Package no longer supported. Contact [email protected] for more info.
[2/4] 🚚  Fetching packages...
[3/4] 🔗  Linking dependencies...
warning " > [email protected]" has unmet peer dependency "popper.js@^1.14.3".
[4/4] 📃  Building fresh packages...
success Saved lockfile.
✨  Done in 19.30s.

Info

Please run buffalo info and paste the information below where it says "PASTE_HERE".

### Buffalo Version
v0.12.6

### App Information
Pwd=/Users/nicholasduffy/.gvm/pkgsets/go1.10.4/global/src/github.com/duffn
Root=/Users/nicholasduffy/.gvm/pkgsets/go1.10.4/global/src/github.com/duffn
GoPath=/Users/nicholasduffy/.gvm/pkgsets/go1.10.4/global
Name=duffn
Bin=bin/duffn
PackagePkg=github.com/duffn
ActionsPkg=github.com/duffn/actions
ModelsPkg=github.com/duffn/models
GriftsPkg=github.com/duffn/grifts
VCS=
WithPop=false
WithSQLite=false
WithDep=false
WithWebpack=false
WithYarn=false
WithDocker=false
WithGrifts=false

### Go Version
go version go1.10.4 darwin/amd64

### Go Env
GOARCH="amd64"
GOBIN=""
GOCACHE="/Users/nicholasduffy/Library/Caches/go-build"
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="darwin"
GOOS="darwin"
GOPATH="/Users/nicholasduffy/.gvm/pkgsets/go1.10.4/global"
GORACE=""
GOROOT="/Users/nicholasduffy/.gvm/gos/go1.10.4"
GOTMPDIR=""
GOTOOLDIR="/Users/nicholasduffy/.gvm/gos/go1.10.4/pkg/tool/darwin_amd64"
GCCGO="gccgo"
CC="clang"
CXX="clang++"
CGO_ENABLED="1"
CGO_CFLAGS="-g -O2"
CGO_CPPFLAGS=""
CGO_CXXFLAGS="-g -O2"
CGO_FFLAGS="-g -O2"
CGO_LDFLAGS="-g -O2"
PKG_CONFIG="pkg-config"
GOGCCFLAGS="-fPIC -m64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -fdebug-prefix-map=/var/folders/4g/dp5nynm51n9dktt40ccngvf40000gn/T/go-build044237569=/tmp/go-build -gno-record-gcc-switches -fno-common"

### Node Version
v8.11.4

### NPM Version
5.6.0

### Yarn Version
1.9.4

### PostgreSQL Version
pg_ctl (PostgreSQL) 10.3

### MySQL Version
mysql  Ver 14.14 Distrib 5.7.21, for osx10.13 (x86_64) using  EditLine wrapper

### SQLite Version
3.19.3 2017-06-27 16:48:08 2b0954060fe10d6de6d479287dd88890f1bef6cc1beca11bc6cdb79f72e2377b

### Dep Version
could not find a Gopkg.toml file

### Dep Status
could not find a Gopkg.toml file

[paganotoni]

@duffn thanks for reporting this issue, i'm willing to work on it unless you want to, do you ?

[duffn]

Please go ahead. 👍

[paganotoni]

Covered in #1280