software/theia: switch gopls for go support

Not much tested but it looks working

software/theia/software.cfg

@@ -13,13 +13,7 @@ extends =
    ../../component/java-jdk/buildout.cfg
    ../../stack/slapos.cfg
    ../../stack/monitor/buildout.cfg
-   ./gowork.cfg
    ./buildout.hash.cfg
-# this gowork.cfg includes the one from caddy, because they share the only gowork
-# workspace (not intentionnaly, as far as I see there's only one gowork per SR)
-# it is included after caddy, otherwise only caddy is installed. The problem of this
-# approach is that caddy's version will be the one pinned here, so we have to update
-# here as well.
 
 parts =
   theia-wrapper
@@ -298,26 +292,12 @@ mode = 0644
 
 
 [gowork]
-# Install go-language-server in workspace
-# Note that this is the same workspace as caddy.
-# install list comes from https://github.com/theia-ide/go-language-server/blob/d259749c8f263c4d845055833b03b1d2dbefa5b3/README.md#prerequisites
-install +=
-  github.com/ramya-rao-a/go-outline
-  github.com/acroca/go-symbols
-  github.com/nsf/gocode
-  github.com/rogpeppe/godef
-  golang.org/x/tools/cmd/godoc
-  github.com/zmb3/gogetdoc
-  golang.org/x/lint/golint
-  github.com/fatih/gomodifytags
-  github.com/uudashr/gopkgs/cmd/gopkgs
-  golang.org/x/tools/cmd/gorename
-  sourcegraph.com/sqs/goreturns
-  github.com/cweill/gotests/...
-  golang.org/x/tools/cmd/guru
-  github.com/josharian/impl
-  github.com/haya14busa/goplay/cmd/goplay
-  github.com/davidrjenni/reftools/cmd/fillstruct
+golang = ${golang1.14:location}
+
+[gowork.goinstall]
+command =
+  bash -c ". ${gowork:env.sh} && GO111MODULE=on go get golang.org/x/tools/gopls@v0.4.3"
+
 
 [cli-utilities]
 PATH = ${nodejs:location}/bin/:${bash:location}/bin/:${fish-shell:location}/bin/:${tig:location}/bin/:${vim:location}/bin/:${tmux:location}/bin/:${git:location}/bin/:${curl:location}/bin