Debian Wheezy is EOL since 31st May 2018, mirrors are disabled now.

Development branch is now named master, so
update conditions for extended extended checks on
Travis.
Also, set new repo name.

Fixes #4027.

Fixed Mojave Mac build with setting MACOSX_DEPLOYMENT_TARGET environment
variable for LuaJIT's Makefile. This variable specifies the minimum
version of OS X on which the target binaries are to be deployed.

The reason why we need to set MACOSX_DEPLOYMENT_TARGET to at least 10.6
is that 10.4 SDK (which is set by default in LuaJIT's Makefile) is not
longer included in Mac OS X Mojave 10.14.

See also https://github.com/LuaJIT/LuaJIT/issues/484

We already set -Wl,-macosx_version_min,10.6 (-macosx_version_min and
MACOSX_DEPLOYMENT_TARGET are synonymous), but it affects only a linker.
We possibly should remove -macosx_version_min, because it superseded by
MACOSX_DEPLOYMENT_TARGET, but it should be done with verification that
the original problem really fixed by the new way to set a deployment
target. This is not part of this patch.

Removed virtualenv usage in CI for OS X (so pip just installs packages
into a system), because OS X Mojave 10.14 does not offer virtualenv by
default.

Fixed #3797

These distributions are past EOL.

Disabled LTO builds, tarballs and packages building on short-term
branches.

Removed 'allow_failures' on coverage / debug build.

Replaced matrix expansion with the list of jobs (because Travis-CI
documentation says it does not support condition jobs with matrix
expansion).

Fixes #3755.

Closes: #3761

The idea behind this change is to have 2x (and maybe later 3x, 4x, ...)
bucket for alpha and beta releases. See more details about the release
process in the documentation: [1].

[1]: https://tarantool.io/en/doc/2.0/dev_guide/release_management/

Main branch was renamed to master.
Update .travis.yml accordingly.

Replaced targets generation using a matrix expansion + exclusion list
with the explicit targets list. Gave meagingful names for targets.

Fixes #3673.

We made a mistake when tagging 1.7.5, which confused git describe.
Now we have added more tags and the hack with removal can be deleted.

- Remove old versions of Fedora and Ubuntu
- Add Fedora 26 and Fedora 27

Patch removes Ubuntu Precise from Travis's testing matrix,
since it uses really outdated GCC v.4.6.x.

Switched from ubuntu zesty to artful, since zesty is EOLed on 13Jan2018

Remove all non-LTS versions of Ubuntu.

PackageCloud doesn't support Ubuntu Artful yet.

Follow up e3d97f6d

Closes #2805

Travis images are broken by design.

Ubuntu Trusty on Travis is buggy.

Fixes #2752

Ubuntu Trusty on Travis is buggy.

Fixes #2752

git describe picks 1.7.5 as a closest tag on 1.8 branch.
Temporary remove 1.7.5 tag to fix 1.8.x packages.

* Switch to PackPack for packages
* Use `packagecloud` deployment for packages instead of travis.sh script
* Use `script` deployment for sources instead of travis.sh script
* Package all branches, but upload only 1.6/1.7
* Move all Travis CI script into the single Makefile

Rumprun is a toolchain to build unikernels based on NetBSD/Rump kernel.
Compiled images can be booted on KVM/XEN and even on "bare metal".

Unfortunally, Tarantool unikernels are still not fully functional due to
bugs in libeio and LuaJIT. However, now we have a simple way to check
cross-compilation for BSD/Rumpkernel and to bake unikernels from the code:

    OS=rumprun DIST=hw packpack
    qemu-system-x86_64 -enable-kvm -kernel build/tarantool-1.7.3.265.img