Update UI and add view feature

[huanghao1998]

What's change:

1. Implement new command: view
2. Improve UI/UX of the SOCket

Functional

Logic.java, LogicManager.java

• Add getViewedPerson(): To get a person that user wants to view their detail information
• Add setViewedPerson(): Set the person that the user wants to view

ViewCommand.java, ViewCommandParser.java

• Similar to delete; parse and identify the selected index and update the viewPerson attribute in model class

AddressBookParser.java

• Add case for view command

Model.java, ModalManager.java

• Add getViewedPerson(): To get a person that user wants to view their detail information
• Add updateViewedPerson(): update the viewPerson attribute such as only this particular person is in the list

Add test for ViewCommand and ViewCommandParser

UI/UX

Update MainWindow:

• Shift the command input and result display to the bottom of the page
• Split the initial contact table into split table:
  1. Show brief information of the contact such as index, name, github username(display "Not available" when its empty) and tags
  2. Show all the information about the person
     Add personDetailCard, personDetailPane: to display the detailed information of the person that is selected

Minor change on the CSS

[codecov]

Codecov Report

Merging #108 (d8fb207) into master (949e33e) will decrease coverage by 1.52%.
The diff coverage is 33.76%.

@@             Coverage Diff              @@
##             master     #108      +/-   ##
============================================
- Coverage     77.84%   76.33%   -1.52%     
- Complexity      599      612      +13     
============================================
  Files            87       91       +4     
  Lines          1729     1796      +67     
  Branches        229      235       +6     
============================================
+ Hits           1346     1371      +25     
- Misses          327      369      +42     
  Partials         56       56              

Impacted Files	Coverage Δ
...rc/main/java/seedu/address/logic/LogicManager.java	65.21% <0.00%> (-9.79%)	⬇️
src/main/java/seedu/address/model/Model.java	100.00% <ø> (ø)
src/main/java/seedu/address/ui/MainWindow.java	0.00% <0.00%> (ø)
src/main/java/seedu/address/ui/PersonCard.java	0.00% <0.00%> (ø)
...c/main/java/seedu/address/ui/PersonDetailCard.java	0.00% <0.00%> (ø)
.../main/java/seedu/address/ui/PersonDetailPanel.java	0.00% <0.00%> (ø)
...rc/main/java/seedu/address/ui/PersonListPanel.java	0.00% <0.00%> (ø)
...rc/main/java/seedu/address/model/ModelManager.java	98.21% <85.71%> (-1.79%)	⬇️
...java/seedu/address/logic/commands/ViewCommand.java	100.00% <100.00%> (ø)
.../seedu/address/logic/parser/AddressBookParser.java	100.00% <100.00%> (ø)
... and 1 more

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more

[huanghao1998]

The codecov failes is because most of the misses came from GUI and it is very hard to test.

[cmang12]

Overall, LGTM 👍

[cmang12]

just a slight suggestion for consistency maybe can put 'Languages: ' and 'Tags' in front