Compatibility with Erlang 20

Updated the travis setup, and updated rebar3

Author: bieniusa

.gitignore

@@ -1,7 +1,7 @@
 _build/
 test/.rebar3/
-TEST-file_"antidote_crdt.app".xml
+TEST-*.xml
 *.swp
 src/*.swp
 test/*.swp
-*.beam
+*.beam

.travis.yml

@@ -2,6 +2,7 @@ language: erlang
 otp_release:
   - 18.3
   - 19.1
+  - 20.1
 install:
   - mkdir -p ~/.config/rebar3/
   - echo "{plugins, [rebar3_proper]}." > ~/.config/rebar3/rebar.config

rebar3

@@ -1,38 +1,5 @@
-#  -------------------------------------------------------------------
-#
-#  Copyright (c) 2014 Basho Technologies, Inc.
-#
-#  This file is provided to you under the Apache License,
-#  Version 2.0 (the "License"); you may not use this file
-#  except in compliance with the License.  You may obtain
-#  a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-#  Unless required by applicable law or agreed to in writing,
-#  software distributed under the License is distributed on an
-#  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
-#  KIND, either express or implied.  See the License for the
-#  specific language governing permissions and limitations
-#  under the License.
-#
-#  -------------------------------------------------------------------
-
-#  -------------------------------------------------------------------
-#  NOTE: This file is is from https://github.com/basho/tools.mk.
-#  It should not be edited in a project. It should simply be updated
-#  wholesale when a new version of tools.mk is released.
-#  -------------------------------------------------------------------
-
-REBAR            = $(shell pwd)/rebar3
-REVISION 		    ?= $(shell git rev-parse --short HEAD)
-PROJECT         ?= $(shell basename `find src -name "*.app.src"` .app.src)
-DEP_DIR         ?= "deps"
-EBIN_DIR        ?= "ebin"
-
-.PHONY: compile-no-deps test docs xref dialyzer-run dialyzer-quick dialyzer \
-		cleanplt upload-docs
-
+.PHONY: compile-no-deps test docs xref dialyzer \
+		
 compile-no-deps:
 	${REBAR} compile skip_deps=true