* build: bump PPAs to Go 1.13 (via longsleep), keep Trusty on 1.11
* travis, build, vendor: use own Go bundle for PPA builds
* travis, build, internal, vendor: smarter Go bundler, own untar
* build: updated ci-notes with new Go bundling, only make, don't test
* build: add support for different package and binary names
* build: bump up copyright date
* build: change default PackageName to empty string
* build, internal, swarm: enhance build/release process
* build: hack ethereum-swarm as a "depends" in deb package
* build/ci: remove redundant variables
* build, cmd, mobile, params, swarm: remove VERSION file; rename Version to VersionMeta;
* internal: remove VERSION() method which reads VERSION file
* build: fix VersionFilePath to Version
* Makefile: remove clean_go_build_cache.sh until it works
* Makefile: revert removal of clean_go_build_cache.sh
This commit tweaks the debian packaging tool:
* All build environment metadata can now be overriden on the command
line. This allows testing the CI build behaviour locally.
* -unstable packages now actually contain the binaries (oops)
* packages use Go 1.7 to build
* archiving is skipped for PR builds
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.