Backport all build-related commits from master to stable-0.2

This is a squash of the following commits that are required to
make gitiles buildable with the latest bazel:

9374f0a - Remove bazel-genfiles from .gitignore
bd0c596 - Use bazelisk as first choice for mvn.sh
9d5cb21 - Replace references to bazel-genfiles with bazel-bin
268d677 - Bazel: Bump bazel version to 1.0.0
03cd750 - Bazel: rules_python must be loaded now
10641da - Upgrade bazlets to latest master revision
06d3ee0 - Bazel: Introduce .bazelversion and update to 0.29.1
3de4f96 - Format all build files with buildifier
a267c30 - Bazel: Add fixes for --incompatible_load_java_rules_from_bzl
4d4432d - Upgrade bazlets to latest master revision
422d67a - Align Eclipse settings with Eclipse 2019.06
008bf1b - Update bazlets to latest revision on master

Change-Id: I4894d7beee21a0ea4bfd92c6ce3c6bf6477ef639

lib/BUILD

diff --git a/lib/BUILD b/lib/BUILD
index ab56df4..e1f4654 100644
--- a/lib/BUILD
+++ b/lib/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/guice/BUILD

diff --git a/lib/guice/BUILD b/lib/guice/BUILD
index 1e60d10..188f2cc 100644
--- a/lib/guice/BUILD
+++ b/lib/guice/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/jetty/BUILD

diff --git a/lib/jetty/BUILD b/lib/jetty/BUILD
index 2c97028..5517d65 100644
--- a/lib/jetty/BUILD
+++ b/lib/jetty/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/jgit/BUILD

diff --git a/lib/jgit/BUILD b/lib/jgit/BUILD
index f2c7435..d813fd7 100644
--- a/lib/jgit/BUILD
+++ b/lib/jgit/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/junit/BUILD

diff --git a/lib/junit/BUILD b/lib/junit/BUILD
index 3445f53..7c03dd3 100644
--- a/lib/junit/BUILD
+++ b/lib/junit/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/slf4j/BUILD

diff --git a/lib/slf4j/BUILD b/lib/slf4j/BUILD
index b619aaa..2719aa8 100644
--- a/lib/slf4j/BUILD
+++ b/lib/slf4j/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/soy/BUILD

diff --git a/lib/soy/BUILD b/lib/soy/BUILD
index 5666b8c..9bf2a39 100644
--- a/lib/soy/BUILD
+++ b/lib/soy/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )

lib/truth/BUILD

diff --git a/lib/truth/BUILD b/lib/truth/BUILD
index 22b79cf..5a57e6d 100644
--- a/lib/truth/BUILD
+++ b/lib/truth/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 java_library(
     name = "truth",
     visibility = ["//visibility:public"],