Fix #562: Use /usr/bin/env bash for the shebang

/bin/bash will not work on OSes which do not have bash as default shell, e.g.,
*BSD. Use common env with bash from PATH to launch scripts.

Author: michael-o

bin/build_drone.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 RELEASE=$(grep 'sdkmanVersion' config.groovy | sed 's_sdkmanVersion = __g' | tr -d "'")
 

bin/build_travis.sh

@@ -1,3 +1,3 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 ./gradlew -Penv=production clean test assemble

bin/download.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 CANDIDATE="$1"
 VERSION="$2"

bin/release-binary.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 BRANCH="$1"
 BUILD_NUMBER="$2"

bin/release.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 VERSION="$1"
 BRANCH="production"

bin/run.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 if [ -z $(which java) ]; then
 	echo "Please install java before continuing..."

src/main/bash/sdkman-availability.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 #
 #   Copyright 2012 Marco Vermeulen

src/main/bash/sdkman-broadcast.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 #
 #   Copyright 2012 Marco Vermeulen

src/main/bash/sdkman-current.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 #
 #   Copyright 2012 Marco Vermeulen

src/main/bash/sdkman-default.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 
 #
 #   Copyright 2012 Marco Vermeulen