[Embed] Fix codesigning issues when targets have spaces

Fix for lint codesign failure on macOS projects

This small change fixes an issue with `{target}-frameworks.sh`, wherein spaces in the target cause a `No such file or directory` error. The fix is simple: wrap `code_sign_if_enabled` in quotes. Works in my local env and hope it works in yours too 👍

Fixes and closes CocoaPods/CocoaPods#6153.

Bump the master submodule to a post-sharding commit

[SourcesManager] Remove const_missing hack

It's been months, time for this hack to go

[Spec::Lint] Fail gracefully when downloading podspec fails

Raise an exception if unable to find a reference for a path and handle symlink references

Escape spaces in CONFIGURATION_BUILD_DIR when creating header folders symlink

Re-escaped backslashes in embed_frameworks generator

[README] Made capitalization and wording consistent 🌈

Thought I'd submit a small PR for the sake of consistency!

0d889c8c seems to have undone the escaped quotes, making them just regular bash quotes. This breaks app paths that have spaces in them.

This patch re-escapes the backslashes that escape the quotes in the generated bash (wow, that's a mouthful).

Release 1.2.0.beta.1

# gpg: Signature made Thu Oct 27 23:09:55 2016 CDT using RSA key ID 15DDA856
# gpg: Good signature from "Samuel Giddins <segiddins@segiddins.me>"
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 7B19 37A9 CF66 AEF6 52C9  4090 0119 5BB3 15DD A856