Add pre_package event to wp8 project

WP7 project was already done in commit: bd2c667e947b3fda05541e0d1a124d23df60a132
Wait for the pre_package event to finish, or the update_csproj function might give unexpected results.
Fixes both the wp7 and wp8 parser.
Code style (indentation)
CB-5125: replace child process exec with spawn
CB-5125 add tests for chil process spawn
CB-5183 WP7/8 custom_path is not correctly resolved by CLI
[CB-5147] emulate needs a space before error message
[CB-5142] improve grammar of emulate description
[CB-4976] Don't symlink into ~/.cordova/lib for local libs

If the user specifies a local URI in his config.json, we don't want to
symlink that lib into $HOME/.cordova/lib, just use it in-place as the
source of the platform.

lazy_load calls now return a promise for the path to the target, and all
logic in other modules that was recomputing the path into the global lib
directory has been fixed to just use that return value. This is more
flexible and supports this feature nicely.
CB:5187 on node  windows broken compile, emulate, run
CB-5187: remove unused var os_platform
increased version of plugman to 0.14.0 in package.json
[CB-5197] Updated version and RELEASENOTES.md for release 3.1.0-0.2.0
[CB-5220] "An error occurred" is missing an "A" ...
[CB-5220] "An error occurred" is missing an "A" ...
[CB-4994] Update xcode dependency to handle Xcode 5 capabilities.
Merge branch 'CB-5183' of https://github.com/sgrebnov/cordova-cli
readability + code quality in wp7+8 parsers
merging
serve: provide basic entry point

Index:
* List included platforms (and available platforms)
* List included plugins
* List package name, id, version

* Provide directory redirects
* Implement directory browsing