CB-6923 Adding support to handle relative paths

Added support to resolve relative paths.
When the path received is relative, it will combine and obtain a full
path before it becomes proceced by IsolatedStorageFile and determine if
exists.

Two private methods were added to handle this, it won't affect the
regular workflow if the path is absolute and it will combine it as
usual.
Merging to work on top of test framework changes
Merging to work on top of relative paths change
added documentation for manual tests
Fixes multiple mobilespec tests errors
Adds Windows platform
This closes #56
Merge branch 'CB-6923' of https://github.com/martincgg/cordova-plugin-file
Added new js files to amazon-fireos platform.
rebase from master
cb-6724changed style detail on documentation
Overwrite existing file on getFile when create is true
CB-7375: CB-6148: Ensure that return values from copy and move operations reference the correct filesystem
Merge remote-tracking branch 'rodrigo/overwrite-create'
CB-7413 Adds support of 'ms-appdata://' URIs
CB-7375: Partial revert to resolve WP8 failures
[CB-7417][File tests] added proper matcher to compare fullPath property

Specs : 111, 112 & 121-124, were using [toBe, toEqual] to compare a
fullPath property from an Entry.
The right matcher to use is toCanonicallyMatch, that it makes a fair and
right comparison across platforms.

In addition, special case to compare Windows Phone entries, was removed.
[CB-7418][DirectoryEntry] Added fullPath variable as part of condition

As well as NativeURL property, the fullPath variable should be part of
the condition to avoid that a null value becomes a path, by adding a
slash at the end of the undefined string.
So in order to add a slash to it, fullPath should contain a value.
Merge branch 'CB-7418' of https://github.com/martincgg/cordova-plugin-file
[CB-7419][WP8] Added support to get metada from dir

The error CODE 1, in the callback it was about the a failed attempt to
get the size of a directory using IsolatedStorageFileStream, get that
information, throwing a SystemException 'DirectoryNotFoundException'.
Instead IsolatedStorageFileStream to get that information from a
directory, now uses Application.GetResourceStream, to that information
from the provided path, only if directory. If other file it would use
'IsolatedStorageFileStream'