Remove benchmarks for Mul to scrap vector dependency - mul is O(1) anyway and never on a critical path

* Support only GHC >= 8.0

* Fix a build warning

* Make integer-simple flag redundant

Kubo Kovac authored 7 years ago and Herbert Valerio Riedel committed 6 years ago

if we only need to run a few benchmarks,
e.g. `text-benchmarks Pure/drop/Text+tiny`
it's wasteful to initialize all of them
(and read all the test data in memory - all
the test data is a few hundreds of MB, but
we read it in several tests, as different types,
and most seriously, as String - which turns this
into GBs of memory)

I used the code from the gist as the source for the Concat module.

france.html is not available in the test data. Commenting out the corresponding
benchmark for now so that benchmarking does not fail.

Benchmarks to:
1) prove that stream after unstream fusion works
2) measure the overhead of stream followed by unstream

Progress towards gh-81.

--HG--
extra : rebase_source : 0559da50e2b5d43f46e4c4baa9f4b5457e8781da
extra : amend_source : 1c20c33aa19bece776361953371efc46d0ec236e
extra : histedit_source : a7aba7dd23ae5f886fd41e3f0856da129165c878

Since encodeUtf8_2 wins under all circumstances, there's no reason
to keep the intermediate version around.

Not surprisingly, this is a lot faster than encodeUtf8_1 and the
Builder-based rewrite under almost all circumstances.

It's slower on tiny inputs (20%), but roughly twice as fast as
encodeUtf8_1 on longer inputs.

--HG--
extra : amend_source : 093410e1295572be039d87a9c21e97d250c5f9f9

These require at least the following version of the text-test-data, dated January 6:

git: 2183e3e5423fbf0d9d0187a4455df699c5e04b74
hg:  6c0e2b527bbbc6e18c622e452d16634b5d953b34

--HG--
rename : Data/Text/Lazy/Encoding/Fusion.hs => Data/Text/Internal/Lazy/Encoding/Fusion.hs
rename : Data/Text/Lazy/Fusion.hs => Data/Text/Internal/Lazy/Fusion.hs
rename : Data/Text/Lazy/Search.hs => Data/Text/Internal/Lazy/Search.hs
extra : amend_source : 2c28ab48f28c6a5750a180a503e1efec634253ea

This provides a nice performance boost!