Various env var fixes, tweaks, and shell boot speed up

shell/golang.sh

@@ -2,5 +2,27 @@
 # Go (golang) environment setup.
 #
 
-export GOPATH="$HOME/.go"
-path_append "$GOPATH/bin"
+export GOPATH="$HOME/.go:$HOME/Projects/Go"
+path_prepend "$HOME/Projects/Go/bin:$HOME/.go/bin"
+
+install_go_global_packages () {
+  local packages=(
+    github.com/golang/lint/golint \
+    github.com/kisielk/errcheck \
+    github.com/kr/pretty \
+    github.com/laher/goxc \
+    github.com/mdempsky/unconvert \
+    github.com/motemen/gore \
+    github.com/nsf/gocode \
+    github.com/pmezard/go-difflib/difflib \
+    github.com/rogpeppe/godef \
+    github.com/tools/godep \
+    golang.org/x/tools/cmd/goimports \
+    launchpad.net/gorun \
+  )
+
+  for package in "${packages[@]}"; do
+    echo "installing/updating \"$package\""
+    go get -u "$package"
+  done
+}