More more docs (#4197)

* Updated docs + some small code changes

* Added validating code doc for developers

* Doc updates

* Updates and improvements

scripts/pre-commit.php

@@ -0,0 +1,36 @@
+#!/usr/bin/env php
+<?php
+
+$failed = false;
+
+if (version_compare(PHP_VERSION, '5.6') >= 0) {
+    $lint = `find . -path './vendor' -prune -o -name "*.php" -print0 | xargs -0 -n1 -P8 php -l | grep -v '^No syntax errors detected' ; test $? -eq 1`;
+} else {
+    $lint = `find . -regextype posix-extended -regex "\./(lib/influxdb-php|vendor)" -prune -o -name "*.php" -print0 | xargs -0 -n1 -P8 php -l | grep -v '^No syntax errors detected' ; test $? -eq 1`;
+}
+
+if (!empty($lint)) {
+    echo "lint check has failed\n";
+    print_r($lint);
+    $failed = true;
+}
+
+$phpcs = `./vendor/bin/phpcs -n -p --colors --extensions=php --standard=PSR2 --ignore=html/lib/* --ignore=html/plugins/ html`;
+
+if (!empty($phpcs)) {
+    echo "PSR2 check has failed\n";
+    print_r($phpcs);
+    $failed = true;
+}
+
+$phpunit = `./vendor/bin/phpunit`;
+
+if(!strstr($phpunit, "OK")) {
+    echo "phpunit tests have failed\n";
+    print_r($phpunit);
+    $failed = true;
+}
+
+if ($failed === false) {
+    echo "Tests ok, submit away :)\n";
+}