don't install LICENSE.txt to /usr/LICENSE.txt (or $PREFIX)

[asottile-sentry]

resolves #714

data_files is intended to be used to place manual files in the output. the intended mechanism for including the license in the distribution is the license_file or license_files options -- I picked the former since it has further compatibility

before:

$ CPATH="$(brew --prefix librdkafka)/include" LDFLAGS="-L$(brew --prefix librdkafka)/lib" bash -xc 'git rev-parse HEAD && rm -rf venv && virtualenv venv -qq && venv/bin/pip install -qq . && ls -al venv'
+ git rev-parse HEAD
e7e066120f05ca6f9c37b18d77f974f1a6cad222
+ rm -rf venv
+ virtualenv venv -qq
+ venv/bin/pip install -qq .
+ ls -al venv
total 44
drwxr-xr-x  8 asottile staff   256 May 12 09:30 .
drwxr-xr-x 25 asottile staff   800 May 12 09:30 ..
lrwxr-xr-x  1 asottile staff    93 May 12 09:30 .Python -> /Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.8/Python3
-rw-r--r--  1 asottile staff    40 May 12 09:30 .gitignore
-rw-r--r--  1 asottile staff 32984 May 12 09:30 LICENSE.txt
drwxr-xr-x 20 asottile staff   640 May 12 09:30 bin
drwxr-xr-x  3 asottile staff    96 May 12 09:30 lib
-rw-r--r--  1 asottile staff   528 May 12 09:30 pyvenv.cfg

after:

$ CPATH="$(brew --prefix librdkafka)/include" LDFLAGS="-L$(brew --prefix librdkafka)/lib" bash -xc 'git rev-parse HEAD && rm -rf venv && virtualenv venv -qq && venv/bin/pip install -qq . && ls -al venv'
+ git rev-parse HEAD
4c6328c314a8c7366950161eaf161c0b89f49558
+ rm -rf venv
+ virtualenv venv -qq
+ venv/bin/pip install -qq .
+ ls -al venv
total 8
drwxr-xr-x  7 asottile staff 224 May 12 09:30 .
drwxr-xr-x 25 asottile staff 800 May 12 09:30 ..
lrwxr-xr-x  1 asottile staff  93 May 12 09:30 .Python -> /Library/Developer/CommandLineTools/Library/Frameworks/Python3.framework/Versions/3.8/Python3
-rw-r--r--  1 asottile staff  40 May 12 09:30 .gitignore
drwxr-xr-x 20 asottile staff 640 May 12 09:30 bin
drwxr-xr-x  3 asottile staff  96 May 12 09:30 lib
-rw-r--r--  1 asottile staff 528 May 12 09:30 pyvenv.cfg

note that the license is still distributed but is now correctly part of the installation metadata:

$ find venv/ -name LICENSE.txt | grep confluent
venv/lib/python3.8/site-packages/confluent_kafka-1.8.3.dist-info/LICENSE.txt

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[asottile-sentry]

@mhowlett (apologies for the direct ping!) any chance this can get a review?

[asottile-sentry]

@pranavrth perhaps ? been setting on this one-liner for ~4 months now and would like to get rid of /usr/LICENSE.txt from showing up :)

[asottile-sentry]

@emasab perhaps?

[dirkmueller]

duplicate of #713

[asottile-sentry]

@dirkmueller your force push here is a little shady -- my patch existed a whole year before yours used my approach: #713 (comment)

[asottile-sentry]

absolutely ridiculous