Since mercury fixed the issue on their code [1], we can drop the
temporary patch we were using to avoid handles reset.

Due to the mercury fix The follwing two issues have been solved:
 - Mercury: https://github.com/mercury-hpc/mercury/issues/272
 - Margo: https://xgitlab.cels.anl.gov/sds/margo/issues/47

[1]: https://github.com/mercury-hpc/mercury/commit/9512b8b04c265645f95fd99f3b9c015e836c0347

They fixed a potential race condition:

https://github.com/mercury-hpc/mercury/commit/a421ea3072c79b2edb6d4d9d2bdaf179b5ef14f3

Changes have been merged upstream [1] with commit `acb8c296a694d7e3e06756e7a102a9d1c92df0c8`.
There is no more need to patch margo to expose enanched init function.

[1]: https://xgitlab.cels.anl.gov/sds/margo/merge_requests/9

`gflags` is an optional dependency of RocksDB, it is used only for cli
tools that we don't use.

As discussed here:
https://xgitlab.cels.anl.gov/sds/margo/issues/43

There is no more need to clone the fork repository of argobots. We could
directly use the original one because all the patches required for margo
have been merged upstream.

changelog for the new version:
https://github.com/facebook/rocksdb/releases/tag/v5.15.10

Mercury now support shared memory autorouting.

A single margo instance can be initialized and it will handle both
shared memory communication and remote ones.

If the endpoint of the RPC is local mercury will automatically use
shared memory.

Since there is only one margo instance all the duplicated code for
rpc/ipc have been unified and simplified considerably.

------

The way in which client contact the server has changed.

 - Server initializes its own margo instance and generate the endpoint
communication string using `HG_Addr_self`.
 - This endpoint description string is written on the pid file
 - When the client library loads it will fetch the server endpoint
description from the pid file and will use that to contact the server.

Also removed mercury_cci_verbs_lookup patch, because it has been merged upstream [1]

[1]: https://github.com/mercury-hpc/mercury/pull/206

margo, argobots and mercury have been updated. The abt-snoozer dep
required by margo it is not needed anymore.

RocksDB has been also updated to the lastest release

compile/download scripts need to exit with positive error code on wrong parameters

Problem: If one of the donwload task fails the script do not stop and
the other task continue to donwload sources.

Solution: If one of the task fails, print an informative error message
and send a signal to the parent process that kills all the spawned tasks
and exits with error code.

When rocksdb is build with jemalloc linking with adafs was failing

The download script do not work if the specified output path
contains more then 1 non-existing folder.
This is due to the -f flag used in the readlink command.
We now use the less strict -m one.

Source folder was removed if existed before but never recreated

Since the download of sources are performed in parallel, we cannot use
anymore a single log file.

The output of the download commands has been reduced to errrors only and
it will be outputted directly on stderr. Thus the log file stuff have been
completely removed.

Moreover the clonedeps function now takes the REPO as second parameter
and additional (non mandatory) git flags as fourth parameter.

Additional fixes have been introduced to run commands in script mode
(-q, -f, ...)

For dependencies in which a specific tags is specified we can download
the code snapshot instead of cloning the whole repo.

Perform all the download and git clone action in parallel using several
processes.

Due to the new parallel use of the clonedeps and wgetdeps functions,
some adjustment to printed message has been made. Now the function write
on stdout only once when they complete.

The specific version is necessary for local I/O to work.

See https://xgitlab.cels.anl.gov/sds/margo/issues/40 for reference of the issue.

5.10.2 -> 5.10.3

5.10.2 couldn't be compiled with gcc 7 due to a rocksDB bug [1]

[1]: https://github.com/facebook/rocksdb/issues/3486

The download script can be used to update dependencies source code by
pull the new version and performing a checkout to that version.
Without forcing (-f) the checkout files that have been modified or
patched won't be updated correctly.