Update UI to be more user-friendly

[rlrh]

Resolves #161 Resolves #177

Summary of changes:

• Add navigation sidebar
  • 4 buttons for Reading List, Archives, Discover and Feeds match List, Archives, Results and Feeds context respectively
  • Executing a context-switching command highlights the button associated with the new context
  • Clicking a button executes the associated default command
  • Reading List: list
  • Archives: archives
  • Discover: googlenews
  • Feeds: feeds
• Redesign Entry cards
  • Make index display bigger and separate from title to support CLI-first policy
  • Move tags below title, description and link
• Use custom fonts
  • Roboto Light for body text
  • Roboto Slab for headings

[coveralls]

Pull Request Test Coverage Report for Build 855

• 41 of 67 (61.19%) changed or added relevant lines in 6 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.6%) to 84.407%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/main/java/seedu/address/logic/parser/GoogleNewsCommandParser.java	0	1	0.0%
src/main/java/seedu/address/ui/MainWindow.java	10	11	90.91%
src/main/java/seedu/address/ui/NavigationBar.java	28	31	90.32%
src/main/java/seedu/address/logic/LogicManager.java	0	21	0.0%
<!--	Total:	41	67	61.19%	-->

Totals
Change from base Build 836:	-0.6%
Covered Lines:	2176
Relevant Lines:	2578

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💛 - Coveralls

[epicfailname]

There is a bug, though I cannot figure out what is causing it. To reproduce:

1. Click Archives button
2. Enter list command
3. Click Archives button

The result display is not updated for step 3

[rlrh]

There is a bug, though I cannot figure out what is causing it. To reproduce:

1. Click Archives button
2. Enter list command
3. Click Archives button

The result display is not updated for step 3

Should be fixed with latest commit

[qjqqyy]

With reference to this thread, an issue in JavaFX's CSS font loader means that our custom font will not get loaded when there is a space character in the application path, like for example

Apr 11, 2019 2:07:01 AM com.sun.javafx.css.StyleManager loadStylesheetUnPrivileged
INFO: Could not load @font-face font [file:/C:/Users/Qi%20Ji/IdeaProjects/ab4/out/production/resources/fonts/RobotoSlab-Regular.ttf]

As this only happens in development under specific circumstances I suggest we don't bother working around it.

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Note that running the shadowJar (or using the gradle task runShadow) works.

[rlrh]

With reference to this thread, an issue in JavaFX's CSS font loader means that our custom font will not get loaded when there is a space character in the application path, like for example

Apr 11, 2019 2:07:01 AM com.sun.javafx.css.StyleManager loadStylesheetUnPrivileged
INFO: Could not load @font-face font [file:/C:/Users/Qi%20Ji/IdeaProjects/ab4/out/production/resources/fonts/RobotoSlab-Regular.ttf]

As this only happens in development under specific circumstances I suggest we don't bother working around it.

Note that running the shadowJar (or using the gradle task runShadow) works.

Thanks for this! Fortunately in this case it still fails gracefully by reverting to a default system font.