Edit typo and missing fullstops for javadocs

[codecov[bot]]

Codecov Report

Merging #252 (e6f4c16) into master (e6758d1) will not change coverage. The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #252   +/-   ##
=========================================
  Coverage     74.14%   74.14%           
  Complexity      579      579           
=========================================
  Files            88       88           
  Lines          1895     1895           
  Branches        220      220           
=========================================
  Hits           1405     1405           
  Misses          409      409           
  Partials         81       81           

Files	Coverage Δ
...va/seedu/address/logic/commands/FilterCommand.java	94.73% <ø> (ø)
...eedu/address/logic/parser/FilterCommandParser.java	91.66% <ø> (ø)
...main/java/seedu/address/model/company/Company.java	81.08% <ø> (ø)
...rc/main/java/seedu/address/model/company/Role.java	82.60% <ø> (ø)