[release/1.4.11] build: add ci.go, use it everywhere

The new build script, ci.go, replaces some of the older shell scripts.
ci.go can compile go-ethereum, run the tests, create release archives
and debian source packages.

(cherry picked from commit 6c33ba14a4)

build/deb.changelog

@@ -0,0 +1,5 @@
+{{.Name}} ({{.VersionString}}) {{.Distro}}; urgency=low
+
+  * git build of {{.Commit}}
+
+ -- {{.Author}}  {{.Time}}