Fix Mac packager to build proper application bundle and include Client icon about blocklypropclient

[PropGit]

Can not determine what is causing the problem here. Will release without this fix for now.

Update: This was found to be a problem with the macos.spec file used by the PyInstaller build step. See next post.

[PropGit]

Found that the cause of all these problems was ultimately due to a malformed macos.spec file.

Determined that the file could be recreated, the proper bundle format requested, the application icon included and the bundle identifier specified using pyi-makespec --windowed --icon BlocklyPropClient.icns --osx-bundle-identifier com.ParallaxInc.BlocklyPropClient --noupx BlocklyPropClient.py

Afterwards, a few modifications to the .spec were required to include the propeller-tools files, the about.txt, and set the application version number.

All this was done in PR #67.

The ugly details will be moved from the README.me to the repo's wiki soon.

[PropGit]

Once we get Issue #66 addressed, I will test more on my machine and then organize a test of a couple other machines.

[PropGit]

Removed one manual change to the .macos.spec file (to leave the Mac application bundle version number unset- 0.0.0) and moved that responsibility over to the mac_app_sign_and_package script - a more fitting place for it. This was done in PR #74.

[PropGit]

Issue #66 completed and PR #74 merged. Build for Mac produces a application bundle which works properly until it's installed and launched with the normal means: from Finder or LaunchPad. This seems to be an issue with retrieving the home directory to convert the relative Propeller-Load executable path to an absolute path, described in this BlocklyProp Issue, which, it turns out, is really a Client issue.

[PropGit]

PR #77 fixed above failure. The call to retrieve the working (application's) directory was responding with blank. Note this problem seems to still exist on Linux as of Issue #82.

Tested on 2 host machines (@PropGit, @MatzElectronics) and two VMs (Yosemite and Sierra). App Bundle and packager deemed correct and ready for release.