Squiz/Documentation: minor consistency fixes

* Verified that the contents of `<standard>` elements is consistently indented (with four spaces).
* Verified that all `<code>` `title` attributes use proper capitalization and punctuation and are prefixed with "Valid" or "Invalid".

Author: jrfnl

src/Standards/Squiz/Docs/Arrays/ArrayDeclarationStandard.xml

@@ -10,12 +10,12 @@
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: array keyword lowercase">
+        <code title="Valid: Array keyword lowercase.">
         <![CDATA[
 $array = array('val1', 'val2');
         ]]>
         </code>
-        <code title="Invalid: first letter capitalised">
+        <code title="Invalid: First letter capitalised.">
         <![CDATA[
 $array = Array('val1', 'val2');
         ]]>
@@ -27,15 +27,15 @@ $array = Array('val1', 'val2');
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: first key on second line">
+        <code title="Valid: First key on second line.">
         <![CDATA[
 $array = array(
           'key1' => 'value1',
           'key2' => 'value2',
          );
         ]]>
         </code>
-        <code title="Invalid: first key on same line">
+        <code title="Invalid: First key on same line.">
         <![CDATA[
 $array = array('key1' => 'value1',
           'key2' => 'value2',
@@ -49,15 +49,15 @@ $array = array('key1' => 'value1',
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: aligned correctly">
+        <code title="Valid: Aligned correctly.">
         <![CDATA[
 $array = array(
          <em> </em>'key1' => 'value1',
          <em> </em>'key2' => 'value2',
          );
         ]]>
         </code>
-        <code title="Invalid: keys and parenthesis aligned incorrectly">
+        <code title="Invalid: Keys and parenthesis aligned incorrectly.">
         <![CDATA[
 $array = array(
          <em>'</em>key1' => 'value1',
@@ -72,15 +72,15 @@ $array = array(
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: keys and values aligned">
+        <code title="Valid: Keys and values aligned.">
         <![CDATA[
 $array = array(
           'keyTen'<em>    </em>=> 'ValueTen',
           'keyTwenty'<em> </em>=> 'ValueTwenty',
          );
         ]]>
         </code>
-        <code title="Invalid: alignment incorrect">
+        <code title="Invalid: Alignment incorrect.">
         <![CDATA[
 $array = array(
           'keyTen'<em> </em>=> 'ValueTen',
@@ -95,7 +95,7 @@ $array = array(
     ]]>
     </standard>
     <code_comparison>
-        <code title="Valid: comma after each value">
+        <code title="Valid: Comma after each value.">
         <![CDATA[
 $array = array(
           'key1' => 'value1',
@@ -104,7 +104,7 @@ $array = array(
          );
         ]]>
         </code>
-        <code title="Invalid: no comma after last value">
+        <code title="Invalid: No comma after last value.">
         <![CDATA[
 $array = array(
           'key1' => 'value1',

src/Standards/Squiz/Docs/Classes/LowercaseClassKeywordsStandard.xml

@@ -1,7 +1,7 @@
 <documentation title="Lowercase Class Keywords">
     <standard>
     <![CDATA[
-    The php keywords class, interface, trait, extends, implements, abstract, final, var, and const should be lowercase.
+    The PHP keywords class, interface, trait, extends, implements, abstract, final, var, and const should be lowercase.
     ]]>
     </standard>
     <code_comparison>

src/Standards/Squiz/Docs/ControlStructures/LowercaseDeclarationStandard.xml

@@ -1,7 +1,7 @@
 <documentation title="Lowercase Control Structure Keywords">
     <standard>
     <![CDATA[
-    The php keywords if, else, elseif, foreach, for, do, switch, while, try, and catch should be lowercase.
+    The PHP keywords if, else, elseif, foreach, for, do, switch, while, try, and catch should be lowercase.
     ]]>
     </standard>
     <code_comparison>

src/Standards/Squiz/Docs/Functions/LowercaseFunctionKeywordsStandard.xml

@@ -1,7 +1,7 @@
 <documentation title="Lowercase Function Keywords">
     <standard>
     <![CDATA[
-    The php keywords function, public, private, protected, and static should be lowercase.
+    The PHP keywords function, public, private, protected, and static should be lowercase.
     ]]>
     </standard>
     <code_comparison>

src/Standards/Squiz/Docs/WhiteSpace/LanguageConstructSpacingStandard.xml

@@ -1,7 +1,7 @@
 <documentation title="Language Construct Whitespace">
     <standard>
     <![CDATA[
-    The php constructs echo, print, return, include, include_once, require, require_once, and new should have one space after them.
+    The PHP constructs echo, print, return, include, include_once, require, require_once, and new should have one space after them.
     ]]>
     </standard>
     <code_comparison>

src/Standards/Squiz/Docs/WhiteSpace/ScopeKeywordSpacingStandard.xml

@@ -1,7 +1,7 @@
 <documentation title="Scope Keyword Spacing">
     <standard>
     <![CDATA[
-    The php keywords static, public, private, and protected should have one space after them.
+    The PHP keywords static, public, private, and protected should have one space after them.
     ]]>
     </standard>
     <code_comparison>