CB-6299 [wp8] Strip protocol and leading slashes from XHRLOCAL URL

(cherry picked from commit 3dbe46184c5846653dc553ea8984d1736380f0bc)
wp8.1 and the IE11 WebBrowser control do not support execScript, moving to 'eval'

(cherry picked from commit 18ec1c3af674007e48bf34dcdf3fc7ee0be8ba10)
[CB-6763] Fixes issue when multiple simultaneous requests are sent.

(cherry picked from commit efaf559ae846567e68e4d96446c8760c3ceed8fc)

Conflicts:
	wp8/template/cordovalib/XHRHelper.cs (Resolved)
Remove unwanted slashes and handle Exceptions

(cherry picked from commit 8829719bbbca1e92670f4576f7baa5e6e4701b9a)
 Fix XHRHelper doesn't resolve request using relative file path

- Cordova RTC work item number: 51127
- Apache Cordova Jira issue: https://issues.apache.org/jira/browse/CB-7338
- Markmail or Google Group reference: n/a
- Product PMR: 81056,841,758
- Worklight RTC work item number: 49576
- Associated mobile-spec test: local XHR Tests - cordova-mobile-spec repository, branch 3.1.x. All green over WP 8.1 & 8.0.
- Cherry-pick 3dbe461, 18ec1c3, efaf559, 8829719 (Fix related to this Jira issue - CB-7338), this cherry picks were added to resolve problems over Windows Phone 8.1.
- Description: Windows Phone native side wasn't resolving XMLHttpRequest, the URL provided for an XHR call, at times contains some unwanted extra slashes, like: 'x-wmapp0: /www or //www'. Added regular expresion to the js script code to remove any ----> ':/, ://, :///' , any slash after 'x-wmapp0:', in that way the URI class it will be successfully resolved and provide the requested content. Also try-catch statements were added, over the 'Browser.InvokeScript' statements, to avoid: 'A first chance exception of type 'System.OutOfMemoryException' occurred in Microsoft.Phone.Interop.ni.dll', that stops the application.